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Frequently asked questions

Answers about water testing, equipment selection, installation and maintenance.

Do I need a water analysis before choosing equipment?

The right solution depends on water composition and intended use. For well water, an up-to-date laboratory analysis is an important starting point. Contact us to discuss which parameters to test.

How do I choose suitable water treatment equipment?

Send your water analysis and describe the problem and water demand. For households, include the number of users and peak demand. Industrial applications also require target water quality and capacity.

Does clear water mean it is safe to drink?

Clear water with a pleasant taste may still contain substances or microorganisms that cannot be detected by sight, smell or taste. Use appropriate laboratory testing to assess water safety.

What determines the price of equipment and installation?

The price depends on water composition, required capacity, technology and installation conditions. Send a water analysis and, if possible, photos of the installation area to request a quotation.

What should I consider about the installation area?

Space and connections depend on the equipment. Water supply, drainage, power, frost protection and service access may be needed. Requirements are confirmed for the selected equipment.

How often does equipment need maintenance?

Maintenance intervals depend on the equipment, water quality and usage. Follow the manufacturer’s instructions and agreed service schedule. Consumables depend on the treatment solution.

Questions by topic

Choose a topic or browse all questions about our home and industrial solutions.

For homes

Water treatment for homes

Which water problems do you most often solve in private homes?

Most often we deal with iron-rich, hard, foul-smelling or bad-tasting and microbiologically contaminated well and borehole water. We also install drinking water filters and mechanical sediment filters.

Where should I start if my well water is of poor quality?

Start with an up-to-date laboratory analysis. Send us the results and describe what you notice in the water (colour, odour, sediment, stains). Based on this, we recommend a suitable unit or combination of units.

Do you install equipment throughout Estonia?

Yes. We serve private customers all over Estonia, in both towns and rural areas. The installation date and price are agreed once the site details have been confirmed.

Do you also offer equipment maintenance?

Yes. We offer maintenance for installed equipment as well as consumables such as filter elements and water softening salt. The maintenance interval depends on the equipment and water quality.

Read more: Water treatment for homes →

Iron-rich water

How can I tell if my water contains too much iron?

Typical signs are yellowish or brownish water, rust-brown stains on sinks, toilets and laundry, and a metallic taste. A laboratory analysis shows the exact iron content.

Is iron-rich water harmful to health?

Iron itself is not usually the main health risk, but it worsens the taste, colour and odour of water and damages pipes and household appliances. Manganese or other substances may be present together with iron, so it is worth having the water analysed.

Which equipment removes iron from water?

An iron removal filter oxidises dissolved iron and captures it in the filter media. The right filter is chosen based on iron, manganese, pH and other parameters. If the water is also hard, a combined solution can be used.

How often does an iron removal filter need maintenance?

An automatic filter backwashes itself. The maintenance interval and filter media replacement depend on water composition and consumption, and we recommend checking the unit regularly.

Read more: Iron-rich water →

Hard water

How does hard water show up at home?

Hard water leaves limescale in kettles, water heaters, on taps and shower glass, increases detergent consumption and can dry out skin and hair.

How is water hardness measured?

Hardness is usually measured in German degrees (°dH) or mmol/l. The exact value can be obtained from a laboratory analysis or a quick test. Hardness is one of the key parameters when choosing a water softener.

How does a water softener work?

A water softener uses ion exchange resin to exchange calcium and magnesium ions. The resin is regenerated automatically with brine, which is why the unit needs water softening salt.

How much salt does a water softener use?

Salt consumption depends on water hardness, water consumption and the unit's settings. We recommend using dedicated water softening salt (tablets) and checking the salt level in the brine tank regularly.

Read more: Hard water →

Water with unpleasant smell or taste

Why does my water smell like rotten eggs?

A rotten-egg smell is usually caused by hydrogen sulphide, which is common in borehole water. The smell can also develop in a water heater due to bacterial activity. A water analysis helps identify the cause.

What causes water to taste bad?

A bad taste can be caused by iron, manganese, organic compounds, hydrogen sulphide or chlorine. The right solution depends on the cause, so a water analysis is the starting point.

How can I remove odour from water?

Depending on the cause, aeration, an oxidising filter or an activated carbon filter is used. If the smell is caused by microbes, disinfection may also be needed.

Is water with an odour dangerous to drink?

An odour does not always indicate a hazard, but it may point to contamination. We recommend a laboratory analysis before using the water for drinking.

Read more: Water with unpleasant smell or taste →

Microbiologically contaminated water

How can I find out whether my well water contains bacteria?

The presence of bacteria can only be confirmed by a laboratory analysis (e.g. E. coli, coliform bacteria, enterococci). Water can be clear and odourless even when it is contaminated.

How does a UV unit disinfect water?

A UV unit irradiates the flowing water with ultraviolet light, which damages the DNA of microorganisms and prevents them from multiplying. The method adds no chemicals to the water and does not change its taste.

Is a pre-filter needed before a UV unit?

Usually, yes. Turbidity, iron and sediment reduce the effect of UV radiation, so a mechanical filter and, where needed, iron removal are installed before the UV unit.

What should I do after a flood or well contamination?

Do not drink the water before it has been analysed. The well and water system must be cleaned and disinfected, and the water then analysed again. UV disinfection provides lasting protection.

Read more: Microbiologically contaminated water →

Salty water

Why is my well water salty?

Salinity can come from the influence of seawater in coastal areas, from deeper aquifers or from the soil. Salty water is often caused by high chloride and sodium levels.

Can salty water be treated for drinking?

Yes. Reverse osmosis is suitable for removing dissolved salts and removes most of them. A water softener does not remove salt from water.

Is a reverse osmosis unit suitable for the whole house?

It can be installed for kitchen drinking water or for the whole house. A whole-house solution needs a larger unit and storage tank, and we choose the right solution based on the water analysis and consumption.

Does salty water damage equipment?

High chloride levels can increase corrosion of metals in pipework and equipment. That is why it is worth analysing salinity and treating the water where necessary.

Read more: Salty water →

Mechanical sediment in water

What is mechanical sediment in water?

Mechanical sediment is sand, clay, rust or other solid particles that make water cloudy and build up in pipes, taps and appliances.

How can sediment be removed from water?

Sediment is removed with a mechanical filter: a screen filter, a cartridge filter or a backwashable sand filter. The choice depends on particle size and quantity.

How often does the filter need cleaning or replacing?

It depends on the amount of sediment and water consumption. A screen filter can be washed, while a cartridge filter element is replaced. A pressure drop or weaker water flow is a sign that the filter needs maintenance.

Why install a mechanical filter before other equipment?

A pre-filter protects downstream equipment such as a water softener, iron removal filter or UV unit, extends their service life and ensures better performance.

Read more: Mechanical sediment in water →

Special solutions

When is a special solution needed?

A special solution is needed when the water has several problems at once or a standard unit cannot deliver the desired result, for example high iron and manganese levels combined with hardness and odour.

How is a special solution selected?

We start from the water analysis, water consumption, installation site and the customer's wishes. We then put together a suitable combination of equipment and a quotation.

Is a special solution more expensive than a standard unit?

The price depends on the amount of equipment needed and the scope of installation. We give an exact price after reviewing the water analysis and site details.

Do you install and service special solutions?

Yes. We install and service special solutions throughout Estonia and help set up the system according to the water composition.

Read more: Special solutions →

Drinking water filters

Which drinking water filter is best for my home?

It depends on what you want to remove. An activated carbon filter improves taste and odour, while reverse osmosis also removes dissolved salts and many other substances.

Can a drinking water filter be installed under the kitchen sink?

Yes. Most drinking water filters are installed under the sink, and the drinking water is supplied through a separate tap or through the mixer tap.

How often does the filter need to be replaced?

Filter replacement intervals depend on the type of filter and water consumption. Pre-filters are usually replaced more often than the membrane or main filter. Follow the manufacturer's instructions.

Does a drinking water filter remove bacteria?

Not all filters remove bacteria. If the water contains microbes, UV disinfection or a special membrane filter is suitable.

Read more: Drinking water filters →

For industry

Industrial water treatment

Which water treatment solutions do you offer for industry?

We offer mechanical filtration, iron removal, water softening, reverse osmosis, demineralised water and electrodeionisation systems, UV disinfection, ultrafiltration, laboratory water treatment and removal of specific substances (fluoride, boron, radionuclides).

What information is needed to prepare a quotation?

We need a raw water analysis, the required water quality, capacity (m³/h or m³/day), intended use and information about the installation site. The more accurate the data, the more accurate our quotation.

Do you design the solution around a specific production process?

Yes. Every industrial solution is chosen according to water composition, process requirements and capacity. Where needed, we combine several technologies into one system.

Do you offer maintenance and consumables for industrial equipment?

Yes. We offer system maintenance, consumables and water treatment chemicals so that equipment runs reliably and water quality stays at the required level.

Read more: Industrial water treatment →

Mechanical filter

What does a mechanical filter remove?

A mechanical filter removes solid particles such as sand, silt, rust and other sediment from water. Filtration accuracy depends on the type of filter and filter media.

Which mechanical filters are used in industry?

Screen and disc filters, bag and cartridge filters, and backwashable sand and multimedia filters are used. The choice depends on capacity and particle size.

Does the filter clean itself?

Automatic backwashing filters clean themselves based on pressure drop or a schedule. In cartridge filters, the filter element must be replaced.

Why is a mechanical filter important upstream of other equipment?

Mechanical prefiltration protects reverse osmosis membranes, UV units and ion exchange resins from clogging and extends their service life.

Read more: Mechanical filter →

Iron removal

Why is iron removal important in industry?

Iron and manganese cause deposits in pipework and equipment, impair product quality and shorten the life of membranes and ion exchange resins.

Which iron removal methods do you use?

We use aeration and oxidation combined with filtration, catalytic filter media and, where needed, chemical oxidation. The method is chosen based on the water analysis.

Which water parameters are needed to choose iron removal?

Iron and manganese content, pH, oxygen content, permanganate index and the required capacity are important.

Can iron removal be combined with other solutions?

Yes. Iron removal is often followed by water softening, reverse osmosis or disinfection, depending on water quality requirements.

Read more: Iron removal →

Water softening

Why is water softening necessary in industry?

Hard water causes limescale in boilers, heat exchangers and equipment, reduces energy efficiency and increases maintenance and repair costs.

How does an industrial water softener work?

Ion exchange resin removes calcium and magnesium from the water. Duplex systems allow continuous production of soft water even during regeneration.

Which data is needed to choose a water softener?

We need the water hardness, capacity, peak load, operating mode and the required residual hardness.

How much salt does an industrial water softener need?

Salt consumption depends on hardness and water volume. We calculate it when preparing the quotation and also supply water softening salt.

Read more: Water softening →

Reverse osmosis

What does reverse osmosis remove from water?

A reverse osmosis membrane removes most dissolved salts, ions, organic substances, bacteria and viruses.

What is reverse osmosis used for in industry?

Reverse osmosis is used to produce boiler feed water, process water, water for the food industry and laboratories, and demineralised water.

Does reverse osmosis require pretreatment?

Yes. To protect the membranes, mechanical filtration, iron removal, softening or antiscalant dosing is usually needed, depending on the water.

How long do the membranes last?

Membrane life depends on feed water quality, pretreatment and maintenance. Regular cleaning and monitoring extend their service life.

Read more: Reverse osmosis →

Demineralised water

What is demineralised water?

Demineralised water is water from which dissolved minerals and ions have been removed. Its purity is usually measured by electrical conductivity (µS/cm).

How is demineralised water produced?

Demineralised water is produced with ion exchange, reverse osmosis, electrodeionisation or a combination of these, depending on the required purity.

Where is demineralised water used?

It is used as boiler water, in laboratories, in the electronics and pharmaceutical industries, in surface coating, at car washes and in batteries.

What do you need to know to choose a system?

We need a raw water analysis, the required conductivity or purity class, the capacity and how the water will be used.

Read more: Demineralised water →

Electrodeionisation (EDI)

What is electrodeionisation?

Electrodeionisation (EDI) is a technology that removes ions from water using ion exchange resin, membranes and an electric field. The resin regenerates continuously without chemicals.

What advantage does EDI have over conventional ion exchange?

EDI does not need regeneration with acid and caustic, continuously produces ultrapure water of consistent quality and reduces chemical handling.

Does EDI require pretreatment?

Yes. EDI is usually installed after reverse osmosis so that the water reaching it already has low salinity.

Where are EDI systems used?

EDI systems are used in the energy sector, pharmaceuticals, the electronics industry and laboratories, where water with very low conductivity is required.

Read more: Electrodeionisation (EDI) →

UV disinfection equipment

How does a UV unit disinfect water?

UV radiation damages the DNA of bacteria, viruses and protozoa so that they cannot multiply. No chemicals are added to the water.

Where is UV disinfection used in industry?

UV disinfection is used in drinking water treatment, the food and beverage industry, fish farming, process water and the treatment of reused water.

What is needed to choose a UV unit?

We need the flow rate, the UV transmittance (UVT) of the water and information on turbidity, iron and manganese. These affect the required UV dose.

How often does the UV lamp need to be replaced?

The replacement interval depends on the lamp type and manufacturer, usually about once a year. The quartz sleeve must be cleaned regularly.

Read more: UV disinfection equipment →

Laboratory water treatment

What kind of water do laboratories need?

Depending on the analysis, laboratories need water of different purity classes (e.g. type I, II or III). Ultrapure water is required for sensitive analyses.

How is laboratory water produced?

Laboratory water is produced with a combination of reverse osmosis, ion exchange, electrodeionisation, UV treatment and ultrafiltration.

How is water purity monitored?

Water purity is monitored by measuring conductivity or resistivity and, where needed, TOC and microbiological parameters.

What do you need to know to choose a system?

We need the required water type, daily water volume, feed water quality and the laboratory's space and connection options.

Read more: Laboratory water treatment →

Fully automatic sampling system

What is a fully automatic sampling system?

A fully automatic sampling system takes and stores water or wastewater samples automatically according to a set schedule or flow volume, without manual intervention.

Where are sampling systems used?

Sampling systems are used at wastewater treatment plants, industrial companies, water utilities and in environmental monitoring, where regular and reliable sampling is needed.

Can samples be stored refrigerated?

Yes. Many systems have refrigerated sample containers so that samples are preserved until they are taken to the laboratory.

Can the system be connected to a control system?

Yes. The system can usually be integrated with an automation or control system and sampling can be triggered by a signal. We confirm the options for the specific unit.

Read more: Fully automatic sampling system →

Ultrafiltration

What is ultrafiltration?

Ultrafiltration is membrane filtration that removes suspended particles, colloids, bacteria and most viruses from water while leaving dissolved salts in the water.

How does ultrafiltration differ from reverse osmosis?

An ultrafiltration membrane has larger pores. It does not remove dissolved salts, but it operates at lower pressure and with lower energy consumption.

Where is ultrafiltration used?

It is used in drinking water treatment, as pretreatment for reverse osmosis, in water reuse and in the food and beverage industry.

How are UF membranes maintained?

The membranes are cleaned with automatic backwashing and periodic chemical cleaning. The maintenance interval depends on feed water quality.

Read more: Ultrafiltration →

Filtration of other liquids

Which liquids can be filtered?

In addition to water, it is possible to filter, for example, process liquids, coolants, oils, chemicals and liquids used in the food and beverage industry.

How is a filter chosen for another liquid?

We take into account the liquid's composition, viscosity, temperature, chemical compatibility, flow rate and the required filtration accuracy.

Which filters are used?

Bag and cartridge filters, self-cleaning filters and membrane filters are used, depending on the liquid and particle size.

Can filtration help reduce process costs?

Yes. A clean liquid extends the life of equipment and of the liquid itself, reduces downtime and allows the liquid to be reused.

Read more: Filtration of other liquids →

Odour removal

What causes an unpleasant odour in water or air?

Odours are often caused by hydrogen sulphide, organic compounds, ammonia or bacterial activity, both in water and in wastewater and production processes.

Which odour removal methods are used?

Aeration, oxidation, activated carbon filters, biofilters and chemical treatment are used. The method depends on the cause and amount of the odour.

Is activated carbon suitable for odour removal?

Activated carbon effectively binds many odour and taste compounds. The filter media must be replaced from time to time as its binding capacity is used up.

How do you find the cause of the odour?

We start with an analysis of the water or air and a description of the process. Based on that, we recommend a suitable technology.

Read more: Odour removal →

Fluoride and boron removal

Why is fluoride and boron removal important?

Some groundwater in Estonia contains fluoride or boron above the limit permitted for drinking water. Excessive amounts can be harmful to health, so the water must be treated where necessary.

Which methods are used to remove fluoride and boron?

Reverse osmosis, selective ion exchange resins and adsorption media are used. Boron removal may require a dedicated solution or several stages.

How can I find out whether my water has too much fluoride or boron?

A laboratory analysis will show this. The results are compared with the limit values set in drinking water requirements.

Is the solution suitable for water utilities and companies?

Yes. We offer solutions for smaller water utilities as well as industrial companies, based on capacity and water composition.

Read more: Fluoride and boron removal →

Radionuclide removal

What are radionuclides in water?

Radionuclides are naturally occurring radioactive substances (e.g. radium, uranium, radon) that may be present in water from some of Estonia's deeper aquifers.

How are radionuclides removed from water?

Ion exchange, reverse osmosis and special filter media are used. Aeration is suitable for removing radon. The method is chosen based on the analysis.

How can I find out whether my water contains radionuclides?

The radionuclide content and the indicative dose of the water can be determined in an accredited laboratory. For water utilities, this is part of drinking water monitoring.

What should be done with used filter media?

Used filter media and waste may require separate handling in line with regulations. We help find the right handling solution.

Read more: Radionuclide removal →

Products and services for all

Water reuse

What is water reuse?

Water reuse means treating used or collected water (e.g. process water, greywater or rainwater) so that it can be used again, for example in processes, cooling, irrigation or toilet flushing.

Can reused water be drunk?

As a rule, water is reused for technical purposes. Using it as drinking water requires very thorough treatment and compliance with drinking water requirements.

Which technologies are used for water reuse?

Mechanical filtration, ultrafiltration, reverse osmosis and disinfection (e.g. UV) are used. The solution is chosen based on the water composition and intended use.

Is water reuse cost-effective?

Water reuse reduces water consumption and wastewater costs. Payback depends on the water volume, water price and the treatment needed, and we can help you calculate it.

Read more: Water reuse →

PVC pipes

What are PVC pipes used for in water treatment?

PVC pipes and fittings are suitable for connecting water treatment equipment, chemical dosing and industrial pipework because they are corrosion-resistant and withstand many chemicals.

Are PVC pipes suitable for drinking water?

Yes. Pipes and fittings with the appropriate certification must be used for drinking water. We will confirm the right product for your application.

Which sizes and pressure ratings do you offer?

We offer PVC pipes and fittings in various diameters and pressure ratings. Send us the required size, pressure rating and quantity and we will prepare a quotation.

How are PVC pipes joined?

PVC pipes are usually joined with solvent cement, threaded fittings or flanges. The right joining method depends on the system and pressure.

Read more: PVC pipes →

Water treatment chemicals

What are water treatment chemicals used for?

Chemicals are used, for example, for water disinfection, pH correction, coagulation, membrane cleaning and the prevention of limescale and corrosion.

How do I choose the right chemical?

The choice depends on the water treatment system, water composition and objective. We advise on the right chemical and dosing.

Should chemicals be dosed automatically?

In many systems it makes sense to use a dosing pump that adds the chemical in precise amounts according to the water flow. This ensures a stable result and prevents overdosing.

How should chemicals be stored safely?

Keep chemicals in their original packaging in a cool, well-ventilated place out of the reach of children. Follow the safety data sheet and use personal protective equipment.

Read more: Water treatment chemicals →

Water system disinfection

When does a water system need to be disinfected?

Disinfection is needed after a new system is installed, after repairs, flooding or a long shutdown, or when an analysis shows microbiological contamination.

How is a water system disinfected?

The system is filled with a disinfecting solution that is held in the pipework for a set time, after which the system is flushed with clean water. A control analysis is then carried out.

Does disinfection provide lasting protection?

A one-off disinfection destroys microbes at that moment but does not protect against new contamination. A UV unit or dosing system provides lasting protection.

Are the substances used for disinfection safe?

When dosed correctly and after thorough flushing, the water can be used again. Always follow the instructions and check the result with an analysis.

Read more: Water system disinfection →

Water softening salt

What is water softening salt used for?

Water softening salt is used to regenerate the ion exchange resin in a water softener so that the unit can keep removing hardness from the water.

Can ordinary table salt be used?

We do not recommend it. Table salt may contain additives and dust that can clog the brine tank. Use dedicated water softening salt in tablet form.

How often should salt be added?

It depends on water hardness, water consumption and the unit's settings. Check the brine tank regularly and keep the salt level above the water surface.

Do you supply water softening salt?

Yes. We supply water softening salt to both households and industry. Ask for a quotation for the quantity you need.

Read more: Water softening salt →