Reverse Osmosis Systems

A reverse osmosis system provides highly filtered drinking water by using a semi-permeable membrane to reduce a wide range of dissolved contaminants and impurities. Unlike conventional carbon water filters, which are primarily designed to improve taste and odour and reduce specific contaminants, reverse osmosis can reduce many dissolved substances from drinking water, including fluoride, nitrates, dissolved salts and certain heavy metals, depending on the system and membrane used.

Our range of reverse osmosis water filter systems is designed for domestic use in UK homes and includes traditional tank systems, modern tankless models, and pumped and unpumped options. Different systems are available with different membrane capacities measured in gallons per day (GPD), so you can choose a system based on your household's water consumption, available space and incoming water pressure.

Where certification or independent performance testing is available for a particular system or component, we highlight this in the product information so you can make an informed comparison. RO systems also require regular maintenance, including replacement of pre-filters, post-filters and the membrane, so we provide guidance to help you keep your system performing properly.

Most domestic RO systems are installed beneath the kitchen sink and supply purified water to a dedicated drinking water tap. Correct installation and regular filter replacement are important for maintaining performance, so we've also provided links to relevant reverse osmosis articles.

If you're looking for a reverse osmosis water filter for your home and aren't sure which system is right for you, call us on 01352 838 281 or send us a message for expert advice on choosing the most suitable option.

Choosing the Best Reverse Osmosis System for Your Home

With several types of reverse osmosis water filter system for home available, choosing the right one depends on how much water you use, the water pressure in your home and how much space you have available. The best reverse osmosis system for one household may not be the right choice for another.

When comparing an RO water system, we recommend looking at the membrane capacity, whether the system has a storage tank, whether a booster pump is required and whether the system provides any additional filtration or remineralisation.

Reverse Osmosis Systems for Your Home

A domestic reverse osmosis system provides highly filtered drinking water at the point where you need it, usually beneath the kitchen sink. Unlike a whole house filtration system, a home RO water system is designed to treat water for drinking and cooking rather than supplying purified water to every outlet in the property.

A reverse osmosis water filter for home use can be particularly useful if you want to reduce a broad range of dissolved substances from your drinking water. The exact contaminants reduced will depend on the membrane and filtration stages used, so always check the individual system specifications if you have a particular water quality concern.

Our range includes different types of reverse osmosis system for home use, including traditional tank systems, tankless models and systems with booster pumps. This allows you to choose a system based on your water pressure, available space and expected water consumption.

If you're unsure which RO water system is suitable for your home, contact Fountain Filters for advice on choosing the right system.

Tank or Tankless Reverse Osmosis Systems?

One of the biggest decisions when choosing a reverse osmosis drinking water system is whether to choose a traditional tank system or a tankless design.

Tank Reverse Osmosis Systems

Traditional reverse osmosis systems use a storage tank to hold purified water ready for use. The RO membrane produces water relatively slowly, while the storage tank allows a supply of purified water to be available when you open the drinking water tap.

Tank systems can be a good choice where:

• You have sufficient cupboard space beneath the sink
• You want purified water stored and ready to use
• You prefer a well-established RO system design
• Your household has relatively high drinking water demand

The storage tank does take up additional space, so this should be considered when planning an under-sink installation.

Tankless Reverse Osmosis Systems

A tankless reverse osmosis system produces purified water on demand rather than storing it in a separate tank. This can make tankless systems particularly attractive where cupboard space is limited or you prefer a more compact installation.

Modern tankless reverse osmosis systems generally use higher capacity membranes than traditional tank systems and can incorporate booster pumps and electronic controls to improve performance.

A tankless RO filter can be a good choice if:

• You have limited cupboard space
• You prefer an on-demand supply of purified water
• You want to avoid a separate storage tank
• You use a significant amount of drinking or cooking water

Our range includes tankless reverse osmosis systems with different specifications, so check the individual product information carefully before choosing.

For a more detailed comparison, see our guide to tank vs tankless reverse osmosis systems.

Pumped or Unpumped Reverse Osmosis Systems?

The water pressure available in your home is an important consideration when choosing a reverse osmosis water filter system.

Unpumped RO Systems

Unpumped systems rely on your incoming mains water pressure to force water through the RO membrane. Where the available pressure meets the manufacturer's requirements, an unpumped system can provide an effective and straightforward solution.

Always check the minimum pressure requirement for the individual system before ordering.

Pumped RO Systems

A pumped reverse osmosis system incorporates a booster pump to increase the pressure supplied to the membrane.

This can be particularly useful where mains water pressure is too low for an unpumped system. Increasing the pressure can also improve the production rate and efficiency of the RO membrane.

If you're unsure whether your water pressure is suitable, we recommend checking it before purchasing. If you need help deciding between a pumped and unpumped reverse osmosis system, contact us for advice.

Understanding GPD - How Much Reverse Osmosis Water Do You Need?

Reverse osmosis sytems are commonly rated in gallons per day (GPD). This refers to the nominal production capacity of the RO membrane under specified test conditions.

For example, a 75 GPD reverse osmosis system has a membrane with a nominal production capacity of approximately 75 gallons per day under the manufacturer's test conditions.

Actual product in your home can be considerably different. Water pressure, water temperature, incoming water quality, membrane condition and the design of the complete system can all affect performance.

For this reason, GPD should be used as a useful comparison between systems rather than as a guarantee of how much purified water you will produce every day.

For normal domestic drinking and cooking, a 50-100 GPD membrane can provide ample capacity for many households. Higher capacity systems may be appropriate where demand is greater.

Reverse Osmosis Drinking Water Systems

A reverse osmosis drinking water system is normally installed at the point of use, most commonly beneath the kitchen sink. The system treats the water supplied to a dedicated drinking water tap rather than filtering the entire property's water supply.

This makes an RO system particularly suitable when your priority is high level filtration for drinking and cooking water rather than treating every tap in your home.

Reverse osmosis can reduce a broad range of dissolved substances that conventional carbon filtration does not specifically target. Depending on the membrane and system, this can include fluoride, nitrates, sodium, dissolved salts and certain heavy metals.

The precise performance varies between systems, so if you are looking to reduce a particular contaminant, always check the manufacturer's specifications and performance data for the individual product.

What Can a Reverse Osmosis Water Filter Remove?

Reverse osmosis uses a semi-permeable membrane to reduce many dissolved contaminants and impurities from water.

Depending on the system, an RO water filter can reduce substances including:

• Fluoride
• Nitrates
• Sodium
• Dissolved salts
• Certain heavy metals
• Certain PFAS compounds
• Other dissolved substances

The pre-filtration stages also help reduce sediment, chlorine and other substances that could affect taste or damage the RO membrane.

It is important to distinguish between reducing a contaminant and completely removing it. Performance varies according to the membrane, system design and operating conditions.

If you are choosing a reverse osmosis water filter because of a specific contaminant check the published performance data for that particular system.

Reverse Osmosis Installation

Most domestic reverse osmosis water filter systems are installed beneath the kitchen sink and connected to the cold mains supply, a dedicated drinking water tap and a suitable waste connection.

The exact installation requirements depend on the system. Tankless systems can have different plumbing and electrical requirements from traditional tank systems, while pumped systems require a suitable power supply for the booster pump.

Before installation, make sure there is sufficient space beneath the sink for the equipment and, where applicable, the storage tank.

Reverse Osmosis Maintenance and Filter Replacement

Like any water filtration sytem, an RO systems needs regular maintenance to maintain its performance.

Most domestic reverse osmosis systems contain several filtration stages. Pre-filters are replaced periodically to protect the membrane, while the post-filter helps maintain the taste and quality of the finished water.

The RO membrane normally lasts considerably longer than the pre-filters, but its service life depends on factors including water quality, usage and how effectively the pre-filters protect it.

Replacing filters when recommended is important because exhausted pre-filters can reduce the performance and service life of the membrane.

For information on replacement intervals and maintaining your system, see our guide to reverse osmosis.

Certification and Performance Testing

Certification and independent testing can provide useful information when comparing reverse osmosis water filter systems, particularly if you are looking for a system to reduce a specific contaminant.

However, certification does not necessarily mean that every component or every contaminant reduction claim associated with a product has been certified.

Where certification or independent performance testing is available for an individual Fountain Filters product, we provide the relevant information on the product page.

If certification is an important consideration for your purchase, check exactly what has been tested or certified and which performance claims the certification applies to.

How to Choose the Best Reverse Osmosis Water Filter System

There isn't one reverse osmosis water filter that is best for every home. The right system depends on your individual requirements.

Before choosing, consider:

1. Water pressure - do you have sufficient pressure for an unpumped system, or would a booster pump be more suitable?
2. Available space - a traditional tank system needs room for the storage tank, while a tankless reverse osmosis system can provide a more compact installation.
3. Water usage - consider how much purified water your household is likely to use for drinking, cooking and other purposes.
4. GPD capacity - compare the nominal membrane capacity, while remembering that actual production depends on operating conditions.
5. Filtration requirements - if you're concerned about a particular contaminant, check the performance data for the individual RO system.
6. Maintenance - all RO systems require periodic filter replacement. Make sure replacement filters and membranes are readily available.
7. Certification and testing - Where relevant, check the certification and independent testing information provided for the specific system.

if you're unsure which reverse osmosis system is right for your home, contact Fountain Filters for advice. We can help you compare the available options based on your water pressure, available space and filtration requirements.

Why Trust Fountain Filters

Reverse osmosis is a specialist area of water filtration, and choosing the right system isn't simply a matter of selecting the model with the highest GPD rating.

At Fountain Filters, we have specialised in water filtration for many years and understand the practical considerations involved in selecting, installing and maintaining domestic RO systems.

We offer a range of reverse osmosis systems from established manufacturers, including tank, tankless, pumped and unpumped models, allowing you to compare different approaches rather than being limited to one type of system.

We also stock replacement filters, membranes and other components needed to maintain your system over its lifetime.

When you buy from Fountain Filters, you can also benefit from:

• Specialist knowledge of domestic water filtration
• Advice on choosing the right RO system for your requirements
• Clear product specifications and technical information
• Replacement filters and membranes for ongoing maintenance
• UK based customer support
• Help with installation and maintenance advice

If you're unsure which reverse osmosis water filter system is right for your home, we're happy to help you compare the available options.

FAQs

What is a reverse osmosis water filter?

A reverse osmosis water filter uses a semi-permeable membrane to reduce a wide range of dissolved contaminants from water. Domestic RO systems normally combine the membrane with pre-filtration and post-filtration stages to provide highly filtered drinking water at a dedicated tap.

Is reverse osmosis water safe to drink?

Yes. Reverse osmosis systems are widely used to produce drinking water. RO reduces many dissolved substances from water, and some systems include a remineralisation stage to add selected minerals back into the treated water. Always follow the manufacturer's installation and maintenance recommendations to ensure the system continues to perform correctly.

What does a reverse osmosis system remove?

The exact performance depends on the membrane and system, but reverse osmosis can reduce a broad range of dissolved substances, including fluoride, nitrates, sodium, dissolved salts and certain heavy metals. Pre-filters can also reduce sediment and chlorine. If you're concerned about a particular contaminant, check the performance information for the individual system.

How much water does a reverse osmosis system waste?

Reverse osmosis systems produce a stream of concentrated water as part of the purification process. The amount of water sent to waste varies considerably between systems and depends on factors including water pressure, temperature, membrane condition and system design. Modern systems can be considerably more efficient than older RO designs, so check the manufacturer's specifications when comparing models.

How long does a reverse osmosis membrane last?

An RO membrane can last considerably longer than the pre-filters when it is correctly maintained. Its service life depends on factors such as incoming water quality, usage, water pressure and how effectively the pre-filters protect it. Regular filter replacement and correct maintenance can help extend membrane life.

Do I need a pumped or unpumped reverse osmosis system?

This depends mainly on your incoming water pressure. An unpumped system may be suitable where mains pressure meets the manufacturer's minimum requirement. If pressure is too low, a pumped reverse osmosis system with a booster pump may be more appropriate. Check the pressure requirements of the individual system before purchasing.

What does GPD mean on a reverse osmosis system?

GPD means gallons per day and refers to the nominal production capacity of the RO membrane under specified test conditions. A 75 GPD membrane, for example, has a nominal capacity of approximately 75 US gallons per day. Actual production in your home will depend on factors including pressure and water temperature.

Are tankless reverse osmosis systems better than tank systems?

Neither type is automatically better. Tankless systems can be useful where space is limited and provide purified water on demand, while traditional tank systems store purified water ready for use. The right choice depends on your available space, water pressure, household demand and personal preference.

Can I install a reverse osmosis system myself?

Some domestic RO systems are designed for relatively straightforward installation, but the exact requirements vary between models. Connections to the mains water supply, waste system and drinking water tap must be made correctly, and pumped or tankless systems may have additional requirements. If you're not confident carrying out the installation, we recommend using a suitably qualified installer.

Need Help Choosing a Reverse Osmosis System?

With different membrane capacities, tank and tankless designs, pumped and unpumped systems and different filtration options available, choosing the right RO system can seem complicated.

If you're not sure which reverse osmosis system is suitable for your home, contact Fountain Filters for advice. Tell us about your water pressure, available space and what you want to use the filtered water for, and we'll help you identify the most suitable options.