Learn how different water treatment technologies work and when they are most suitable.
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UV disinfection uses ultraviolet light to inactivate bacteria, viruses and other microorganisms. It is commonly used as a final barrier in drinking water and process water systems.
Well Water
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Particle Filtration
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UV Disinfection
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Drinking Water
Filtration is one of the most common water treatment methods and is used to remove particles, turbidity and suspended solids from water. Depending on water quality and treatment goals, anything from simple cartridge filters to sand filters, multimedia filters and membrane systems may be used.
Lake Water
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Mechanical Screening
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Sand Filtration
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Ozone Oxidation
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Activated Carbon Filtration
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UV Disinfection
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Fine filter
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Drinking Water
Well Water
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Aeration
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Iron Filter
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UV Disinfection
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Fine filter
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Drinking Water
Particle Filtration
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Reverse Osmosis
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UV Disinfection
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Drinking Water
Particle Filtration
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Activated Carbon or Ion Exchange
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UV Disinfection
Groundwater is one of the most common raw water sources for drinking water. The water is naturally filtered through soil and bedrock formations, typically resulting in low turbidity and limited microbiological contamination. However, groundwater may contain naturally occurring substances such as iron, manganese, radon, fluoride, hardness minerals and, in some cases, elevated salinity.
Well Water
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Aeration
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Iron & Manganese Filter
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UV Disinfection
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Drinking Water
Well Water
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Aeration / Degassing
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UV Disinfection
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Drinking Water
Groundwater
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Water Softening
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UV Disinfection
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Drinking Water
Groundwater
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Particle Filter
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Reverse Osmosis
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UV Disinfection
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Drinking Water
Ozone is a powerful oxidizing agent used to reduce microorganisms, break down organic contaminants and improve taste, odour and colour in water. Today ozone is widely used in municipal water treatment, food processing, aquaculture, industrial water systems and greenhouse cultivation.
Lake Water
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Screen Filter
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Sand Filtration
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Ozone Oxidation
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Activated Carbon Filtration
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UV Disinfection
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Fine Filtration
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Drinking Water
Source Water
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Particle Filtration
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Ozone Treatment
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Irrigation
Process Water
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Solids Removal
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Ozone
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Degassing
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UV
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Culture Tank
Water
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Ozone
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Activated Carbon
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UV
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Drinking Water
Ozone is a powerful oxidizing agent and should be handled with care. Elevated ozone concentrations in air may irritate the respiratory system, eyes and mucous membranes. Ozone systems should therefore be installed and operated in well-ventilated areas according to the manufacturer’s recommendations. At high concentrations, ozone-enriched water may also cause irritation to skin and sensitive tissues. However, ozone typically decomposes rapidly back into ordinary oxygen after treatment.
Activated carbon is one of the most widely used filtration media in water treatment. The material has an extremely large internal surface area that can adsorb organic compounds, taste, odour and certain environmental contaminants. Activated carbon is often used as a polishing stage following other treatment processes and before final disinfection.
Lake Water
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Screen Filter
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Sand Filtration
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Ozone Oxidation
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Activated Carbon
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UV Disinfection
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Drinking Water
Water
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Activated Carbon
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UV Disinfection
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Drinking Water
Particle Filtration
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Activated Carbon
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Fine Filtration
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UV Disinfection
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Drinking Water
Municipal Water
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Activated Carbon
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Fine Filtration
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Drinking Water
Activated carbon has a limited adsorption capacity and must be replaced or regenerated periodically. A saturated carbon filter will gradually lose treatment performance and may in some cases provide an environment for microbial growth. Proper maintenance is therefore essential for long-term performance.
Reverse osmosis (RO) is a membrane-based water treatment technology used to reduce salts, minerals, fluoride, nitrate, PFAS and many other dissolved substances. Water is forced through a semi-permeable membrane which allows water molecules to pass while rejecting many contaminants dissolved in the water.
Brackish Water
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Particle Filtration
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Fine Filtration
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Reverse Osmosis
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UV Disinfection
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Drinking Water
Seawater
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Screen Filter
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Sand Filtration
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Fine Filtration
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SWRO
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UV Disinfection
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Drinking Water
Groundwater
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Particle Filter
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Reverse Osmosis
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UV Disinfection
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Drinking Water
Particle Filtration
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Fine Filtration
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RO Membrane
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UV Disinfection
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Drinking Water
Reverse osmosis always produces two water streams: permeate (treated water) and concentrate. The concentrate stream contains the contaminants removed from the feed water and must be managed appropriately. RO systems also require regular maintenance and monitoring to ensure long membrane life and consistent water quality.
Ion exchange is a water treatment technology where unwanted dissolved ions are exchanged for other ions attached to a specialized resin. The technology is commonly used in drinking water production, industrial processes and advanced water treatment applications.
Groundwater
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Particle Filtration
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Ion Exchange
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UV Disinfection
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Drinking Water
Particle Filtration
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PFAS Resin
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Fine Filtration
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UV Disinfection
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Drinking Water
Particle Filtration
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Activated Carbon
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Ion Exchange
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Process Water
Ion exchange resins have a limited treatment capacity and require periodic regeneration or replacement. Resin selection must be based on water analysis, as different resins are designed for different contaminants.
Water softening is used to reduce hardness caused primarily by calcium and magnesium. Hard water is generally not a health concern, but it can cause scaling in pipes, water heaters, household appliances and industrial processes.
Groundwater
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Particle Filter
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Water Softener
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UV Disinfection
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Household Water
Well Water
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Aeration
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Iron Filter
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Water Softening
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UV Disinfection
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Drinking Water
Raw Water
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Particle Filtration
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Water Softening
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Process
Water softening does not improve microbiological water quality and is not a substitute for disinfection. The primary purpose is to reduce scaling and protect equipment. Softening systems require regular maintenance and replenishment of regeneration salt.
Iron and manganese are commonly occurring substances in groundwater and well water. Elevated concentrations may cause discoloration, deposits, fouling of pipes, as well as taste and odour issues. These issues are usually aesthetic rather than health related but can significantly affect water quality and equipment.
When iron or manganese is oxidized, it is effectively transformed from a dissolved substance into solid oxygen-containing compounds. Iron forms rust-like particles while manganese forms solid manganese oxides. These particles can then be removed through filtration, which is the basis of most iron and manganese removal systems.
Well Water
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Aeration
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Iron Filter
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Fine Filtration
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UV Disinfection
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Drinking Water
Well Water
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Aeration
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Iron and Manganese Filter
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Fine Filtration
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UV Disinfection
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Drinking Water
Well Water
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Oxidation
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Manganese Filter
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Fine Filtration
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Drinking Water
Iron is often present as dissolved iron in groundwater and may give the water a yellow, yellow-brown, orange or reddish-brown appearance. When exposed to air, the iron oxidizes and forms visible precipitates that can cause staining, sediment and deposits. Analysis of iron, manganese, pH, alkalinity and dissolved oxygen is often important when selecting the appropriate treatment solution.
PFAS is a large group of synthetic compounds used in industrial processes, firefighting foams, surface treatments and consumer products. These substances are characterized by exceptional chemical stability and are often referred to as "forever chemicals". Certain PFAS compounds can accumulate in the environment and living organisms, increasing the need for monitoring, treatment and destruction.
It is important to distinguish between technologies that remove PFAS from water and technologies that actually destroy PFAS molecules. Activated carbon, ion exchange resins, zeolite-based adsorbents and membrane systems typically concentrate PFAS into a filter medium or concentrate stream which must then be managed.
Advanced Oxidation Processes (AOP) and emerging physical destruction technologies are being developed to attack the exceptionally strong chemical bonds found in PFAS compounds. DABCE is actively involved in this field and is working at the forefront of next-generation PFAS destruction technologies aimed at permanently breaking down contaminants rather than simply transferring them elsewhere.
Particle Filtration
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Activated Carbon
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Fine Filtration
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UV Disinfection
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Drinking Water
Particle Filtration
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Zeolite Adsorbent
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Fine Filtration
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Drinking Water
Pretreatment
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RO or Adsorbent
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Concentrate Treatment
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AOP Destruction
PFAS treatment is a rapidly evolving field. Technology selection should always be based on water analysis, PFAS composition, flow rate and treatment objectives. It is equally important to consider how spent media, concentrated PFAS streams and other residuals will be managed after treatment.
Bacteria, viruses and other microorganisms may occur in both private and public water supplies. The risk is typically highest in surface water, shallow wells, poorly protected wells, storage tanks and distribution systems exposed to environmental contamination. Microbiological water treatment aims to reduce or eliminate disease-causing organisms before the water is used for drinking or industrial purposes.
Lake Water
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Screen Filter
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Sand Filter
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Ozone
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Activated Carbon
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UV Disinfection
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Drinking Water
Well Water
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Particle Filter
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UV Disinfection
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Drinking Water
Raw Water
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Filtration
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UV Disinfection
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Storage Tank
Solids Removal
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Ozone
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Degassing
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UV Disinfection
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Culture Tank
Microbiological contamination is rarely visible to the naked eye. Water may appear crystal clear while still containing bacteria, viruses or other microorganisms. Regular water analysis is therefore important, particularly for private wells and smaller water systems.
Radon is a naturally occurring radioactive gas formed during the decay of uranium and radium in bedrock. In some regions, radon can dissolve into groundwater and enter buildings through wells and water systems. The problem is most common in drilled bedrock wells but may occur in other groundwater sources as well.
Well Water
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Aeration / Degassing
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UV Disinfection
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Drinking Water
Well Water
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Aeration
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Iron Filter
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Fine Filtration
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UV Disinfection
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Drinking Water
Well Water
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Aeration / Degassing
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Iron Filter
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Water Softening
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UV Disinfection
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Drinking Water
Radon in water is invisible, odourless and normally has no impact on taste or appearance. Laboratory testing is the only reliable way to determine radon concentrations. When radon-containing water is used in showers, taps or other household applications, part of the radon may be released into indoor air, which is one reason elevated levels should be addressed. Since aeration and degassing intentionally expose water to air, a downstream hygienic barrier such as UV disinfection is often recommended to reduce the risk of bacterial growth or recontamination before the water is used for drinking.
Lake water and other surface waters are widely used as raw water sources throughout the world. Unlike groundwater, lake water is continuously influenced by weather, seasons, biological activity and human impact. Water quality may therefore vary considerably over time and often requires multiple treatment barriers to achieve the desired quality.
DABCE’s Offgrid Water Treatment System (OWTS) is designed to produce safe water from local water sources without relying on extensive infrastructure. The system can be adapted for lake water, surface water and groundwater by combining treatment stages such as filtration, ozone, activated carbon, UV disinfection and other technologies depending on raw water quality and intended use.
Lake Water
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Screen Filter
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Sand Filter
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UV Disinfection
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Drinking Water
Lake Water
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Screen Filter
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Sand Filter
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Ozone
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Activated Carbon
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UV Disinfection
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Drinking Water
Lake Water
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Screen Filter
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Sand Filter
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Ozone
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Activated Carbon
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Fine Filtration
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UV Disinfection
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Drinking Water
Lake water often contains microorganisms, organic matter and suspended particles that vary throughout the year. For this reason, multiple treatment barriers are commonly used, where filtration reduces particles and UV or other disinfection methods provide microbiological protection.
Brackish water contains more dissolved salts than freshwater but significantly less than seawater. It commonly occurs in coastal regions where groundwater is influenced by seawater or in transition zones between fresh and marine waters. Elevated salinity may affect taste, cause corrosion and impact certain industrial or agricultural applications.
Brackish Water
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Particle Filtration
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Fine Filtration
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RO
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UV Disinfection
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Drinking Water
Brackish Water
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Sand Filtration
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Activated Carbon
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RO
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UV Disinfection
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Drinking Water
Brackish water is highly variable and does not always resemble seawater. Water composition can differ significantly between locations and seasons, making water analysis critical before selecting a treatment solution. In many cases, reverse osmosis is the most effective method for reducing salinity.
Seawater contains significantly higher concentrations of dissolved salts than groundwater or brackish water. Typical seawater contains approximately 35 grams of dissolved salts per litre (35 g/L), with sodium chloride (NaCl) representing the largest fraction. Common dissolved ions include sodium (Na⁺), chloride (Cl⁻), magnesium (Mg²⁺), sulfate (SO₄²⁻), calcium (Ca²⁺), potassium (K⁺), and smaller amounts of bromide (Br⁻) and other trace elements. To produce drinking water or process water from seawater, desalination processes are normally required, with reverse osmosis (RO) being the most widely used technology.
Seawater
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Screen Filter
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Sand Filter
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Fine Filtration
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SWRO
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UV Disinfection
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Drinking Water
Seawater
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Screen Filtration
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Sand Filtration
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Fine Filtration
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ModuPure™ RO
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UV Disinfection
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Drinking Water
Although seawater represents a vast water resource, desalination generally requires more energy than treatment of groundwater or lake water. Proper water analysis and system design are therefore important when selecting a technically and economically suitable solution.
Water analysis is often the most important basis for selecting the correct treatment solution. Many water quality issues are invisible to the naked eye and different contaminants require different treatment methods. By analysing the chemical, physical and microbiological characteristics of water, the appropriate technology can be selected from the start.
Aeration or Ozone
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Iron Filter
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Fine Filtration
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UV Disinfection
Activated Carbon, Ion Exchange or AOP
Water Softening
RO / Desalination
DABCE Cloud is our digital platform for water treatment, water analysis and process support. The platform is used by customers, partners and specialists to collect, analyze and interpret water-related information.
As a DABCE customer, additional features may be available, including analysis tools, technical decision support, documentation, operational information and project-specific resources.
We also publish free knowledge resources and tools on the platform. The knowledge page you are reading right now is an example of content that is available to all visitors.
Chlorination is one of the world’s most widely used water disinfection methods. Chlorine has been used for more than a century to protect drinking water from bacteria, viruses and other microorganisms. Unlike UV disinfection, chlorine also provides residual protection in storage tanks, pipelines and distribution systems.
Raw Water
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Filtration
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UV Disinfection
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Chlorination
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Distribution Network
Filtration
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Chlorination
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Storage Tank
Well Water
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UV Disinfection
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Chlorination
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Storage Tank
Chlorination is often combined with other treatment technologies. UV disinfection, ozone and filtration reduce contaminants and microorganisms, while chlorine provides residual protection in storage tanks and distribution systems. Proper dosing is important because both excessive and insufficient chlorine levels can create problems.
Swimming pool water is continuously exposed to contaminants from bathers, air, rain and the surrounding environment. Maintaining good water quality typically requires a combination of filtration, disinfection and water chemistry control. The goal is to keep the water hygienic, clear and comfortable for users.
One of the most important functions of chlorine in a swimming pool is to provide residual protection between bathers. Whenever multiple people use the same water there is a risk that bacteria, viruses and other microorganisms are introduced into the system. By maintaining an appropriate free chlorine concentration, these microorganisms can be inactivated before they spread to other users.
UV and ozone are highly effective treatment technologies but primarily act within the treatment system itself. Chlorine remains in the pool water and provides continuous protection throughout the entire pool between circulation cycles.
Many people believe that a strong chlorine smell means there is a high concentration of free chlorine in the water. In practice, the opposite is often true. The characteristic "pool smell" is usually caused by chloramines, which are reaction products formed when chlorine reacts with sweat, skin particles, cosmetics, urine and other organic substances introduced by bathers.
Elevated chloramine levels may cause irritation of the eyes and respiratory system and can reduce overall water quality. UV disinfection and ozone are therefore often used as complementary treatment methods to destroy chloramines and other organic contaminants. Periodic water replacement can also help reduce the accumulation of unwanted substances.
By combining filtration with UV and/or ozone treatment, pool owners can often achieve improved water quality, lower chloramine levels and in some cases reduce the need for water replacement. The result is typically clearer water, less odour and a more pleasant swimming experience.
Pool Water
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Sand Filter
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Chlorination
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Pool
Pool Water
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Sand Filter
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UV Disinfection
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Chlorination
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Pool
Pool Water
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Sand Filter
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Ozone
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Chlorination
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Pool
UV and ozone can significantly improve pool water quality, but they normally do not provide residual disinfection in the pool itself. For this reason, a smaller amount of chlorine or another disinfectant is almost always used as a complementary treatment to maintain safe water quality between treatment cycles.
Spas, hot tubs and whirlpools operate with significantly smaller water volumes than traditional swimming pools while often experiencing a much higher bather load. The elevated water temperature, typically 35–40°C, also creates favourable conditions for bacterial growth if water quality is not carefully controlled.
The elevated temperature in spas and hot tubs allows bacteria and biofilm to develop faster than in conventional swimming pools. Regular monitoring of disinfectant levels, pH and filter performance is therefore especially important.
Chlorine can be added in several different ways depending on the size and application of the system. Smaller pools and spas often use chlorine tablets, while larger facilities typically rely on automatic dosing systems. An increasingly popular solution is saltwater pools where chlorine is generated directly in the water using an electrolytic cell.
Many spas use bromine instead of chlorine. Bromine generally performs well at the elevated temperatures found in spas and hot tubs, while chlorine remains the most common disinfectant in conventional swimming pools.
Spa
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Cartridge Filter
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Chlorine or Bromine
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Spa
Spa
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Filtration
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UV Disinfection
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Chlorine or Bromine
↓
Spa
Spa
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Filtration
↓
Ozone
↓
Chlorine or Bromine
↓
Spa
Due to elevated temperatures and often high bather loads, spas and hot tubs generally require more frequent monitoring and maintenance than traditional swimming pools. UV and ozone systems can significantly improve water quality, but should typically be considered a complement to chlorine or bromine rather than a complete replacement.
Aeration and degassing are used to remove unwanted gases from water while simultaneously increasing dissolved oxygen levels. The technology is commonly applied in groundwater and well water treatment where substances such as radon, hydrogen sulfide, carbon dioxide and methane may occur naturally. Aeration is also frequently used as a first step for oxidizing dissolved iron and manganese so that these substances can subsequently be removed by filtration.
Aeration and degassing are often performed in an open or atmospheric tank where water is exposed to air. This allows dissolved gases such as radon, hydrogen sulfide, carbon dioxide and methane to be removed while increasing dissolved oxygen levels. The process can also assist in the oxidation of iron and manganese prior to filtration.
In some systems, aeration is combined with ozone injection. Ozone acts both as a powerful oxidizing agent and as an effective barrier against many microorganisms. The combination of aeration, ozone and downstream filtration can improve odour, colour, microbiological quality and the removal of iron and manganese.
When aeration is used for iron or manganese treatment, these substances are oxidized. In practice this means they are transformed from dissolved substances into solid oxygen-containing compounds. Iron forms rust-like particles while manganese forms solid manganese oxides. These particles can then be removed through filtration.
When water is aerated it is intentionally brought into contact with air. If the treated water is intended for drinking purposes, a downstream hygienic barrier such as UV disinfection is often recommended to reduce the risk of bacterial growth or recontamination within the system.
Brown, yellow or rust-coloured water is a common issue in private wells and some municipal water systems. The discoloration is often caused by iron, manganese, humic substances or corrosion from aging pipes. In some cases the colour is visible immediately, while in others it develops after the water has been exposed to air.
Well Water
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Aeration
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Iron Filter
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UV Disinfection
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Drinking Water
Water
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Sand Filtration
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Ozone
↓
Activated Carbon
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UV Disinfection
↓
Drinking Water
Brown or yellow water can have multiple causes that require different treatment approaches. It is therefore often difficult to select the correct treatment solution based solely on the colour of the water. A water analysis combined with guidance from a qualified water treatment professional is normally recommended before investing in water treatment equipment.
Black deposits, dark staining or black-coloured water are often caused by manganese. Unlike iron, which typically produces brown or rust-coloured deposits, manganese often forms dark brown to black precipitates. The issue is most common in groundwater and private wells.
Well Water
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Aeration
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Iron & Manganese Filter
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UV Disinfection
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Drinking Water
Well Water
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Ozone
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Iron & Manganese Filter
↓
Activated Carbon
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UV Disinfection
↓
Drinking Water
Black deposits are often mistaken for dirt, soot or particles from plumbing systems. Since manganese, iron, corrosion and other contaminants can produce similar symptoms, a water analysis combined with professional water treatment advice is generally recommended before selecting a treatment solution.
White or milky water is often caused by tiny air bubbles formed during pumping, pressure changes or temperature variations within the water system. Because the solubility of oxygen decreases as water temperature increases, dissolved air can form small bubbles when water is warmed or exposed to pressure changes. If the water clears after standing a few minutes in a glass, the issue is typically caused by air bubbles and is generally harmless.
In other cases, white or milky water may be caused by calcium precipitation, other minerals or suspended particles that do not disappear when the water is left standing. If the cloudiness remains after standing in a glass for an extended period, further investigation is recommended.
Groundwater
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Water Softening
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UV Disinfection
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Drinking Water
Well Water
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Degassing
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UV Disinfection
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Drinking Water
If the water clears after standing for a few minutes, the issue is often caused by air bubbles rather than contamination. Persistent cloudiness may instead be related to mineral precipitation or other water quality problems. Water analysis and consultation with a qualified water treatment specialist are recommended when the cause is uncertain.
Cloudy water normally contains small suspended particles that give the water a hazy appearance. Unlike air bubbles, the cloudiness often does not disappear when the water is left standing in a glass. Turbidity may be caused by soil particles, organic matter, precipitated iron or manganese, microorganisms or other contaminants in the source water.
Lake Water
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Screen Filter
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Sand Filter
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UV Disinfection
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Drinking Water
Well Water
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Particle Filter
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Fine Filter
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UV Disinfection
↓
Drinking Water
Cloudy water may be caused by anything from harmless particles to microbiological problems or surface water intrusion. If cloudiness is recurring or appears suddenly, a water analysis and consultation with a qualified water treatment specialist are recommended before selecting a treatment solution.
Sulfur or rotten egg odours are most commonly caused by hydrogen sulfide (H₂S), a gas that may occur naturally in oxygen-poor groundwater and wells. The smell can often be detected at very low concentrations and is considered unpleasant even when levels are relatively low. The issue is common in private wells, particularly where groundwater contains limited dissolved oxygen.
When hydrogen sulfide comes into contact with air or oxidants such as ozone, it can be converted into other sulfur compounds that can subsequently be removed through filtration. For this reason, aeration, degassing, ozone and activated carbon are commonly used to treat these odour problems.
Well Water
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Aeration and Degassing
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Activated Carbon
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UV Disinfection
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Drinking Water
Well Water
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Ozone
↓
Activated Carbon
↓
UV Disinfection
↓
Drinking Water
Rotten egg odours are most commonly caused by hydrogen sulfide, but similar odour issues may also originate from other compounds or microbiological activity. Since the root cause affects the treatment approach, both water analysis and consultation with a qualified water treatment specialist are generally recommended before selecting a treatment solution.
Fishy odours in water are relatively uncommon but may occur in both private wells and municipal water systems. The smell may resemble fish, seafood, marine odours or stale organic material and often becomes more noticeable when the water is heated.
The issue is commonly associated with organic compounds, biological activity or, in some cases, elevated levels of ammonium and nitrogen compounds. Surface water influenced by algae may also contain odour compounds perceived as fishy or earthy. The appropriate treatment method depends on the underlying cause.
Raw Water
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Activated Carbon
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UV Disinfection
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Drinking Water
Raw Water
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Ozone
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Activated Carbon
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UV Disinfection
↓
Drinking Water
Fishy odours may originate from several different causes, including organic compounds, algae, biological activity and internal plumbing issues. Water analysis and consultation with a qualified water treatment specialist are therefore generally recommended before selecting a treatment solution.
Earthy or swamp-like odours are often associated with organic compounds, algae and natural decomposition processes in soil and aquatic environments. The smell may be described as earthy, musty, swamp-like or similar to damp forest conditions and can occur in both surface water and groundwater. Humans are highly sensitive to these odours and may detect them at extremely low concentrations.
Common odour compounds include geosmin and 2-MIB (2-methylisoborneol), which are produced by certain algae, cyanobacteria and microorganisms. These compounds belong to a group of naturally occurring organic substances strongly associated with wetlands, biological activity, decomposition and what many people perceive as “swamp-like chemistry”. While these compounds are normally not considered a direct health concern, they often act as an important warning signal that the water is influenced by organic matter, surface water or microbiological activity. If earthy or swamp-like odours appear suddenly or become significantly stronger, this may also indicate surface water intrusion through a damaged well, leaking pipework or another defect in the water system. Such issues should always be investigated and corrected because they may allow soil particles, organic matter and microorganisms to enter the drinking water supply.
Raw Water
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Activated Carbon
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UV Disinfection
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Drinking Water
Raw Water
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Ozone
↓
Activated Carbon
↓
UV Disinfection
↓
Drinking Water
Earthy and swamp-like odours are often associated with geosmin, 2-MIB, humic substances and other biological activity in aquatic environments. While the odour does not necessarily indicate a health risk, it serves as an important warning signal of organic matter, surface water influence or microbiological activity. If the odour appears suddenly or becomes significantly stronger, wells, pipes and related infrastructure should be inspected for leaks or damage that could allow soil particles, organic matter and microorganisms to enter the water supply. Water analysis and consultation with a qualified water treatment specialist are therefore recommended before selecting a treatment solution.
Salty taste in water is caused by elevated concentrations of dissolved salts. In Sweden, sodium (Na⁺) and chloride (Cl⁻) are the most common contributors, although other salts may also affect taste. Salty water can occur in private wells, municipal systems and technical installations producing drinking water from brackish water or seawater.
Salty taste should often be considered an important warning signal. In private wells, increasing salinity may indicate seawater intrusion, brackish water influence, road salt contamination or changes in the groundwater aquifer. In systems using reverse osmosis (RO) or other desalination technologies, a sudden increase in salt taste may indicate membrane damage, leaks, sensor failures, faulty valves or other operational problems reducing treatment performance. Significant changes in taste should always be investigated.
Raw Water
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Pre-Filtration
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Reverse Osmosis (RO)
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UV Disinfection
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Drinking Water
Raw Water
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Pre-Filtration
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ModuPure™ RO
↓
UV Disinfection
↓
Drinking Water
Salty taste is often more than a simple taste issue. Elevated levels of sodium and other dissolved salts are generally undesirable in drinking water and may affect both taste and health (depending on concentration and consumption). If the salty taste changes over time, the cause should always be investigated. In private wells, increasing salinity may indicate seawater intrusion, brackish water influence or other changes in the groundwater source. In desalination systems based on reverse osmosis (RO) or similar technologies, increasing salt taste may indicate membrane damage, leaks, sensor failures or other operational problems reducing treatment performance. In systems treating seawater or brackish water, this may in severe cases allow water with significantly higher salinity than intended to reach the user. A noticeable increase in salt taste should therefore always be taken seriously and followed up with water analysis and system inspection.
Metallic taste in water is typically caused by elevated concentrations of metals or minerals. Iron, manganese, copper and zinc are common contributors, but corrosion within plumbing systems and water heaters can also cause the issue. The taste may be described as metallic, bitter, blood-like or similar to coins.
In many cases, metallic taste is primarily an aesthetic issue, but it may also indicate changes in water quality or corrosion problems within the plumbing system. If the taste appears suddenly or increases over time, a water analysis should be performed to identify the cause.
Silver has been used for storing water and beverages for thousands of years. Historically, silver vessels were used to keep water fresh long before bacteria and microorganisms were understood. The reason is that silver ions possess natural antibacterial properties. The World Health Organization (WHO) describes silver as an alternative drinking water disinfectant, and silver is still used in certain water treatment products and drinking water systems to limit microbiological growth. Silver is typically applied at very low concentrations and is generally used as a complement to other hygienic barriers rather than as a stand-alone disinfection method.
Many metals occur naturally in water, and several are essential for humans, animals and plants. Iron, copper, zinc and manganese, for example, are required in small amounts for normal biological functions. However, elevated concentrations over long periods may be undesirable and in some cases pose health concerns. For this reason, national and international drinking water standards include limits and guidelines for many metals.
A metallic taste often appears at concentrations far below levels normally associated with health concerns. Taste can therefore serve as an early warning sign of changing water chemistry, corrosion or elevated metal levels. Although the cause may sometimes be natural, new or increasing taste problems should be investigated through water analysis to ensure the water remains suitable for long-term use.
For those interested in more detail, comprehensive guidelines and limit values exist for metals, microorganisms and other drinking water contaminants. In Sweden, drinking water regulations are managed by the Swedish Food Agency, while the World Health Organization (WHO) publishes internationally recognized Guidelines for Drinking-water Quality. These documents are updated regularly and form the basis for much of today’s drinking water quality management.
Well Water
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Aeration or Ozone
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Iron and Manganese Filter
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UV Disinfection
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Drinking Water
Water Analysis
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pH Adjustment
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Replacement of Damaged Components
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Normal Operation
A metallic taste often indicates that metals are dissolving into the water or that corrosion is occurring within the plumbing system. While the taste does not always indicate a health concern, changes in taste should be taken seriously as they may signal changing water chemistry, corrosion or elevated metal concentrations. If the problem appears suddenly or becomes more noticeable over time, water analysis and inspection of plumbing systems are recommended before selecting a treatment solution.
Scale deposits are primarily caused by elevated concentrations of calcium and magnesium in water, commonly referred to as hard water. When water is heated or evaporates, these minerals may precipitate and form white or grey deposits on fixtures, shower screens, heating elements and other surfaces.
Hard water is generally not considered a health concern, and calcium and magnesium are naturally occurring minerals that humans require in small amounts. The challenges are mainly technical. Scale deposits can reduce heat transfer, increase energy consumption, impair valves and equipment, and increase cleaning and maintenance requirements.
In industrial, energy and building management systems, scale deposits are often a far greater concern than in residential applications. Boilers, steam systems, heat exchangers, HVAC systems, cooling systems, heat pumps, humidifiers, process equipment and cooling towers can suffer from deposits that reduce heat transfer efficiency and overall system performance. The result is often higher energy consumption, increased operating costs, shorter equipment lifespan and in some cases unplanned downtime.
For this reason, water treatment technologies such as softening, reverse osmosis, desalination, chemical conditioning and continuous water quality monitoring are commonly used in industrial facilities. Even relatively small amounts of scale can have significant economic consequences over time in larger boiler and steam systems.
Well Water
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Water Softener
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UV Disinfection
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Property
Raw Water
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Water Softening
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Boiler / HVAC / Heat Exchanger
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Efficient Operation
Even a thin layer of scale acts as insulation on heated surfaces. Just a few millimetres of scale on a heating element, inside a water heater or within an industrial heat exchanger can reduce heat transfer efficiency and increase energy consumption. This is one reason why many industries, hotels, buildings and energy facilities invest in water softening even when the water is otherwise perfectly safe to drink.
Scale deposits are typically a technical rather than a health-related issue. Calcium and magnesium are naturally occurring minerals, but elevated concentrations can cause significant deposits in plumbing systems, water heaters, heat pumps, boilers, HVAC systems and other equipment. If scaling becomes problematic, a water analysis is recommended to determine water hardness and identify the most appropriate treatment solution.
Remineralization is used to add minerals back into water after treatment. The process is commonly applied following reverse osmosis (RO), desalination and other membrane processes where a large proportion of the naturally occurring minerals have been removed.
During desalination, not only salts but also calcium, magnesium and other substances contributing to alkalinity and buffering capacity are removed. The result is often very soft water with low mineral content, limited buffering capacity and potentially unstable pH. Remineralization is therefore used to create a more balanced drinking water with improved taste and more stable chemistry.
Many desalination plants invest significant effort removing almost all dissolved substances from water. Afterwards, some minerals are added back through remineralization. The goal is not to achieve the purest water possible, but rather to create a stable, pleasant-tasting and technically balanced drinking water.
When producing drinking water from melted snow, glacier ice or other extremely low-mineral water sources, remineralization can be an important final treatment step. These water sources often contain very low mineral concentrations and limited buffering capacity. Passing the water through mineral or calcite media can improve pH stability, water quality and taste.
The technology can also be relevant for private installations, such as island cottages or properties producing drinking water using RO systems. If the water feels extremely soft or flat, a remineralization bed can provide a more natural taste and more stable water chemistry. Maintenance requirements are generally low because the water mainly passes through a bed of natural minerals or limestone without moving parts.
Brackish Water
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RO
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Remineralization Bed
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UV Disinfection
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Drinking Water
Seawater
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RO
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Remineralization
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UV Disinfection
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Drinking Water
Remineralization is usually not intended to solve a water quality problem, but to improve and stabilize water that has already been treated. In many cases the objective is to achieve the right balance between mineral content, alkalinity, taste and corrosion control.
Slimy deposits in water systems are often caused by biofilm. Biofilm is a thin layer consisting of microorganisms, organic matter and substances produced by the microorganisms themselves. Nearly all water systems develop some degree of biofilm over time, although the extent depends on water quality, temperature, flow conditions and construction materials.
In most cases, biofilm is a natural phenomenon, but excessive growth can contribute to odour problems, discolouration, blockages and reduced hygienic water quality. Biofilm may also provide an environment where other microorganisms can establish and grow more easily.
The small screen located at the outlet of many faucets is not only designed to catch sand, rust and other particles. It often also captures small fragments of biofilm released from the inside of the plumbing system. If you have ever removed a faucet screen or inspected older pipes, you may have noticed a thin slimy layer on the surface. In many cases this is biofilm. The phenomenon is similar to the slippery rocks often found along shorelines and streams, although the microorganisms and biological composition typically differ between natural environments and engineered water systems.
Well Water
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Particle Filter
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UV Disinfection
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Property
Raw Water
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Ozone
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Filtration
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UV Disinfection
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Drinking Water
Some biofilm is present in most water systems and does not automatically indicate unsafe water. However, if slime growth increases, taste or odour problems appear, or the issue develops suddenly, the cause should be investigated. Water analysis, system inspection and consultation with a water treatment specialist can help identify appropriate corrective measures.
Unpleasant odours in water can have many different causes. The smell may be described as musty, earthy, chemical, sewage-like, mould-like or simply unusual. In many cases the cause is related to natural processes in the source water, but odour changes may also indicate problems in wells, plumbing systems, water heaters or other equipment.
Humans are extremely sensitive to odour compounds and can often detect changes long before they become visible in a water analysis. A new or increasing odour should therefore be considered an important indication that water quality or system performance has changed. Even if the cause does not necessarily represent a health risk, it is generally recommended to identify the source.
Raw Water
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Activated Carbon
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UV Disinfection
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Drinking Water
Raw Water
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Ozone
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Activated Carbon
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UV Disinfection
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Drinking Water
Odour issues are often detected long before other water quality problems become apparent. Humans can detect certain odour compounds at concentrations far below levels that cause visible changes in the water. For this reason, changes in odour are often among the earliest signs that something has changed in the water source or treatment system.
If water suddenly develops a new or noticeably stronger odour, the cause should always be investigated. Although many odour issues have natural causes, changes may also be related to leaking wells, surface water intrusion, biofilm growth, equipment faults or other issues requiring corrective action. Water analysis combined with technical inspection is often the fastest way to identify the source of the problem.
Green water can have several different causes. In lakes, ponds and surface waters, algae and biological activity are the most common explanation. In buildings, pools and technical systems, green discoloration may instead be caused by metals, corrosion or chemical reactions. Correct diagnosis is therefore essential before selecting a treatment solution.
Green coloration does not necessarily indicate unsafe water, but a sudden change in colour or clarity should always be investigated. Chemically, green and blue-green shades are often caused by dissolved metal ions or corrosion products. Copper is the most common cause and may produce colours ranging from pale blue to turquoise or green depending on concentration, pH and other water chemistry conditions. Nickel, chromium and certain other metals may also contribute to green colours under specific circumstances. In lakes and reservoirs, however, microscopic algae and cyanobacteria containing natural pigments are often responsible.
Green water in lakes and ponds is often caused by microscopic algae suspended in the water. Under favourable conditions these organisms can reproduce rapidly and create a noticeable green colour. In drinking water systems, however, green shades may instead originate from copper compounds or corrosion products released from plumbing installations.
The colour of water can often provide clues about the underlying chemistry. Copper ions frequently produce blue or turquoise shades, nickel may under certain conditions create green tones, while iron typically causes yellow, orange or brown colours. For this reason, water chemists can sometimes obtain an initial indication of the cause simply by observing the colour, although laboratory analysis is always required for confirmation.
Raw Water
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Filtration
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Ozone
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Activated Carbon
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UV Disinfection
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Drinking Water
Water Analysis
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pH and Corrosion Assessment
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Corrective Actions
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Normal Operation
Green water may have biological, chemical or technical causes. Since the same colour change can originate from very different mechanisms, the root cause should be identified before selecting a treatment solution. Water analysis is often the fastest way to determine whether the issue is related to algae, metals, corrosion or other factors.
Red, orange or reddish-brown water is often caused by iron, natural organic matter or a combination of both. Iron occurs naturally in many groundwater sources and may be completely invisible when dissolved. When exposed to oxygen, iron oxidises and forms particles that produce yellow, orange, red or brown colours. Natural organic matter from soils, forests and wetlands may also contribute yellow, brown or reddish-brown tones.
In many waters, iron and natural organic matter form complexes, meaning that iron ions become bound to organic molecules. These complexes may create intense reddish-brown colours and can make iron more difficult to remove using conventional aeration and filtration. The colour may originate from the water source itself, but also from plumbing systems, water heaters or other installations affected by corrosion. Significant colour changes should therefore be viewed as an indication that water chemistry or infrastructure conditions have changed.
The colour may originate from the water source itself, but also from plumbing systems, water heaters or other installations where corrosion occurs. Just as green colours are often associated with copper, red, orange and brown shades are frequently linked to iron and its oxidation products. Significant colour changes should therefore be seen as an important indication that water chemistry or infrastructure conditions have changed.
Red water is not always caused by rust. Many forested and wetland areas contain large amounts of natural organic matter that gives water a brown or reddish-brown colour. When iron is also present, stable iron-organic complexes may form, creating even stronger colours. These complexes are often more difficult to treat than ordinary iron-rich water. As a result, two waters with the same iron concentration may appear completely different depending on their organic content.
Well Water
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Aeration or Ozone
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Iron and Manganese Filter
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UV Disinfection
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Drinking Water
Water Analysis
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Pipe System Inspection
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Corrosion Mitigation
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Normal Operation
Red or orange water is most commonly caused by iron, but significant colour changes should never be ignored. If the issue appears suddenly, it may be related to changes in the water source, corrosion, maintenance work or other technical issues. Water analysis and technical inspection are therefore recommended before selecting a treatment solution.
Blue-green stains on sinks, showers, toilets and plumbing fixtures are most commonly caused by copper. When copper dissolves from pipes, valves or other components, it can react with substances in the water and form characteristic blue-green deposits. The issue is relatively common in properties with copper plumbing, particularly where water chemistry promotes corrosion.
The colour results from the same fundamental chemistry responsible for the green patina that develops on old copper roofs, statues and copper surfaces. Low pH, low alkalinity, very soft water or otherwise aggressive water chemistry can increase copper dissolution. In some cases, nickel, which is present in many alloys and stainless materials, may also contribute to green colouration if corrosion occurs under unfavourable conditions.
The same copper compounds that create blue-green stains in bathrooms are responsible for the green colour of many historic copper roofs around the world. The colour develops when copper reacts with oxygen, carbon dioxide and other substances in its environment, forming a protective patina. In drinking water systems, similar colours often indicate that water chemistry or corrosion conditions should be investigated.
Water Analysis
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pH Adjustment
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Remineralization
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Reduced Corrosion
Water Analysis
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Pipe System Inspection
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Corrosion Mitigation
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Normal Operation
Blue-green stains are most commonly associated with copper and often indicate that metals are dissolving from plumbing systems. If the issue appears suddenly or increases over time, water analysis and evaluation of pH, alkalinity and corrosion conditions are recommended. Early identification can help protect both infrastructure and water quality.
Low water pressure or reduced flow is one of the most common issues in both residential and commercial water systems. The problem may develop gradually over time or appear suddenly and can be caused by anything from clogged filters and valves to pump failures, corrosion or changes in the water source.
Many people perceive low pressure as a water quality issue, but the cause is often hydraulic rather than chemical. To identify the correct solution, it is important to determine whether the problem affects the entire property or only specific outlets.
Check Strainer
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Inspect Fixture
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Clean or Replace Component
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Normal Operation
Check Pump
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Check Pressure Tank
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Check Filters
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Check Water Source
Many low-pressure problems are caused by surprisingly simple issues. A clogged faucet screen, a partially closed valve or a filter that has not been replaced for a long time can significantly reduce flow. For this reason it is often wise to start troubleshooting with the simplest components before planning larger interventions.
A shower head is often an unexpected source of poor flow or uneven spray patterns. Small nozzles can gradually become blocked by scale, iron deposits or other build-up. A simple first step is to soak the shower head in a vinegar solution for approximately 30 minutes. If the problem is caused by mineral deposits, you may be lucky enough to restore much of the original performance.
In industrial facilities, HVAC systems, process plants and water treatment installations, pressure loss is often an important indicator of system condition. A gradually increasing pressure drop across filters, heat exchangers, membranes, UV systems or pipework may indicate fouling, biofilm growth, scaling or other deposits. Continuous pressure and flow monitoring is therefore commonly used as part of preventive maintenance programs.
Low water pressure is not always a water treatment issue. The cause may just as easily be mechanical or hydraulic. If the problem appears suddenly, affects multiple outlets simultaneously or continues to worsen, the system should be investigated before major investments are made in new equipment.
White spots on glass, shower screens, faucets and other surfaces are most commonly caused by hard water. When water droplets evaporate, dissolved minerals remain on the surface, primarily calcium and magnesium. These minerals form visible white deposits that are sometimes mistaken for dirt, soap residue or cleaning products.
The issue is common in areas with hard groundwater but can also occur in municipal supplies. White spots are normally not a health concern but can be difficult to clean and may create an untidy appearance. Over time, the same minerals may contribute to scale formation in fixtures, water heaters and other equipment.
A simple field test is to apply a small amount of vinegar to the deposit. If it dissolves quickly, scale is often the cause. If there is little or no effect, other minerals such as silica may be involved.
The white spots seen on glass often consist of the same minerals responsible for scale formation in water heaters, heat exchangers and industrial systems. The difference is that scale on glass is mainly an aesthetic issue, while the same minerals may cause major energy losses and maintenance costs in technical equipment.
If the spots disappear easily when treated with vinegar or another mild acid, they are almost always calcium-based mineral deposits. Acids dissolve calcium carbonate and similar carbonate scale very effectively.
Although hard water minerals are the most common cause of white spots, other explanations are possible. White deposits may sometimes consist of silica, aluminium compounds, salt residues or other naturally occurring minerals. Silica stains, for example, are often much more difficult to remove than scale deposits and typically respond poorly to vinegar or other weak acids. As a result, two white deposits that look identical may have very different chemical compositions.
Well Water
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Water Softening
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Property
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Reduced Scale Spots
Raw Water
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Water Softening
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Optimized Water Chemistry
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Reduced Deposits
White spots are normally not a health concern but indicate the presence of naturally occurring minerals in the water. If the issue becomes extensive, or if scale is also forming in water heaters, showers and household appliances, it may be worth analysing the water hardness and evaluating whether water softening is appropriate.
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