We have specialised in drinking water filtration for several years, with a particular focus on gravity-based filtration. Our experience and in-depth knowledge of filtration technology have led us to design and manufacture a filter that is truly effective, tested, easy to use and easy to maintain. You can find out more about the history of the Ultimate Star Filter® on this page.

Based on scientific data and an assessment of water pollution in Europe, we have focused our efforts on filtering pollutants that pose a risk to human health. Discover the performance of the Ultimate Star Filter® and its unique features.

We have classified the main water pollutants into several categories.

Our Ultimate Star Filter® is one of the only gravity filters in the world to have been tested over its entire lifespan (3,000 litres per filter – 6,000 litres for a pair) for microbiology (bacteria, salmonella, viruses) with exceptional results.

You will find all the information about the tests carried out on the analysis results page.

Our Ultimate Star Filter® is one of the only activated carbon-based gravity filters in the world to be NSF® certified.

Our Ultimate Star Filter® complies with European REACH regulations.

Without revealing our manufacturing secrets, and unlike most carbon filters sold under different brand names and composed solely of activated carbon, our filter is a complex assembly of several elements. Our composite filter provides effective filtration of most of the potentially dangerous pollutants present in water.

The filter is moulded from very high quality activated carbons, all NSF certified®, it contains silver ions for their bacteriostatic properties, as well as a specific material that improves the adsorption of heavy metals, also NSF certified. Finally, it incorporates a special nanofiltration membrane that works in conjunction with the other processes to treat a wide range of pollutants, including bacteria and viruses. This membrane was developed by NASA and was initially used to filter water in space for astronauts. It tracks down the smallest molecules, right down to viruses, and its characteristics enable it to filter particles down to 0.001 micrometres (nanofiltration). This component is also NSF® certified.

Other parts of the filter

• The plastic parts of the filter are made from food-grade polypropylene, free from BPA and phthalates. This plastic has been assessed by an independent laboratory and has passed the REACH and ROHS (Restriction of Hazardous Substances) assessment aimed at limiting the use of ten hazardous substances: Lead, Mercury, Cadmium, Hexavalent Chromium, Polybrominated Biphenyls (PBB), Polybrominated Diphenyl Ethers (PBDE), Bis(2-ethylhexyl) phthalate (DEHP), Butylbenzyl phthalate (BBP), Dibutyl phthalate (DBP) and Diisobutyl phthalate (DIBP).
• The silicone used in the joints is food-grade, and has passed REACH and ROHS assessments.
• The glue used to assemble the different parts of the filter is food-grade, and has also passed REACH and ROHS assessments.

Our Ultimate Star Filter® is both NSF® certified and has passed the REACH assessment. To the best of our knowledge, it's the only filter in Europe to combine all these features, and as such we can guarantee unfailing efficiency and safety in use.

The lifespan of the Ultimate Star Filter® has been established at 3000 litres. As each system is used with at least one pair of filters, the useful life of a system is therefore 6000 litres, i.e. an average of 2 years of daily use for a family of 4.

This lifespan is based not so much on the filter's ability to retain pollutants, but more on the reduction in flow rate that is bound to occur with use. The special feature of activated carbon, one of the components of the filter, is that it is made up of very fine micro-channels, enabling pollutants to be retained by a phenomenon known as adsorption. These micro-channels will gradually become blocked by the limescale that can accumulate in them, as well as the various sediments contained in the water.

The time it takes for this phenomenon to appear can vary considerably from one filter to another, depending on how well the filter is maintained and the quality of the water (hardness). Detailed information on flow rate and filter life is given below.

What happens if I exceed the recommended filter life?

There is no risk in using the filter beyond its 3000-litre service life. The only limit will be the water flow rate, which may decrease after 3000 litres, making the filtration time longer over time.

What does this mean in terms of daily use?

It is estimated that you need around 2 litres of water per person per day when used for drinking, making hot drinks (tea, coffee, herbal teas, etc.), cooking pasta, rice, vegetables, etc.

Generally speaking, all you need to know is the volume of your system (6 litres, 8 litres or 12 litres) and how often you fill it to determine the theoretical useful life of the filters.

For example, if you have an 8-litre system and you fill it once a day, the 6000 litres will be reached in : 6000 / 8 / 365 = 2 years.

If you use a 6-litre system and fill it twice a day, the 6000 litres will be reached in : 6000 / (6 x 2) / 365 = 1.3 years.

Please note: this theoretical lifespan depends very much on the way in which maintenance is carried out (frequency of cleaning, storage of the filter in case of absence, etc.) and the quality of the filtered water (tap water or not, limescale content, hardness of the water, presence of sediment, etc.).

Whatever you use your filters for, we recommend changing them every 2 years.

How much does a litre of filtered water cost?

Based on the above data, we estimate that for a pair of filters, the cost per litre of filtered water is around 2 euro cents.

Our filters have been designed to be effective against a wide range of water pollutants, and this has an impact on the flow rate. A compromise has to be found between the contact time of the water (and its pollutants) with the filter media, and the filtration speed.

If the water comes into contact with the filter very quickly, the flow rate will be fast, but filtration will be mediocre most of the time. A very long contact time, which is not necessarily the best choice, normally results in better filtration, but a mediocre flow rate.

We have experimented and chosen a compromise between the two, in order to guarantee the best possible filtration and a flow rate that allows optimum use of the filter.

Over the life of the filter, we were able to establish the following flow rate:

These flow rates may vary depending on the hardness of the water, the quality and frequency of maintenance, whether the water is clean or not, and whether your filters are properly primed.

The minerals in the water are in ionic form. As with most activated carbon filters, minerals in this form are not retained and therefore pass through.

The Ultimate Star Filter® is designed to remove pollutants from water that are harmful to health, but their design allows the minerals to remain in the filtered water.

When you drink water filtered by our systems, you are choosing water that is purified, healthy and pure, while retaining the minerals originally present in the water.

The Ultimate Star Filter® does not filter limescale either. Read our explanation of limescale filtration for more information.

Limestone is naturally present in most water sources. This water, which you get from your tap, comes mainly from groundwater, which is a reserve of rainwater that has infiltrated and become loaded with various minerals as it passes through the rocks in the ground.

The limestone in water is in ionic form and consists mainly of calcium and magnesium carbonate, minerals that our bodies need to stay healthy.

Ultimate Star Filter® filters do not remove limescale, just like the minerals dissolved in water, and that's a good thing for our health.

The limescale in water is therefore an important source of minerals for our bodies and does not need to be removed, unlike by washing machines, dishwashers or coffee makers.

If you have very hard water and your installation includes a water softener, read this topic.

Ultimate Star Filter® filters contain silver in the form of silver ions. These silver ions are integrated into the activated carbon itself, as well as into the filter membrane, in the form of a nanometric support.

Depending on the concentration used, silver can be bactericidal (it kills living organisms) or bacteriostatic (prevents any living organisms - bacteria, viruses - from developing on the filter).

The concentration of silver ions used in our filters is very low and allows a bacteriostatic action, which guarantees that even if your filtered water contains pathogenic living organisms, these will have no way of developing on the filter and thus risk polluting your filtered water.

Ultimate Star Filter® filters are perfectly compatible with most other gravity-fed water filtration systems on the market.

Their size and the diameter of the threaded rod mean they can be installed on a wide range of systems. They are compatible with Berkey, British Berkefeld, Phoenix, PureWell, Weeplow and other systems.

Their filtration performance, well above that of most filters on the market, as well as their NSF certification and compliance with European REACH safety regulations, make them an excellent choice. They're a great way to replace your old filters.

If you have any doubts, don't hesitate to contact us by telephone or via our contact form.

Not only are the components involved in filtration all NSF® certified, but our Ultimate Star Filter® is itself NSF® certified. And we are one of the only manufacturers of activated carbon-based gravity-fed water filters to have this certification.

The main reason for this rarity is that NSF® certification requires not only a study of all the filter components, but also laboratory analyses following a very specific protocol, and last but not least, certification of the production site. These operations take a very long time, require a great deal of preliminary work and are very costly. In addition to the fact that most filters simply couldn't pass NSF® certification due to lack of efficiency, the time and money involved in obtaining this certification puts many brands off. That's why we're all the more proud to have obtained this certification!

Beware of the many brands that display an NSF® logo, even though this often relates to only one component of the filter, or sometimes refers to a product that has nothing to do with it...

In this case, NSF® certification alone is not a guarantee of quality. It only provides certain guarantees about the protocol used for the analyses.

It is also important to look carefully at the results of the analyses provided and the way in which they were carried out (standards used, pollutant concentrations, etc.).

Our analyses, on the other hand, were carried out according to the rules, in compliance with the standards and concentrations.

As a further guarantee of safety, our filter complies with European REACH regulations, proving that no hazardous materials are used in our filter.

The main aim of the European REACH (Registration Evaluation and Authorisation of Chemicals) regulation is to improve knowledge of the many chemical substances in circulation. Manufacturers, users and importers of these substances located in the EU must undergo REACH testing.

At Star Water Filter®, we take safety and environmental issues very seriously.

That's why all our relevant components have passed the REACH tests, and the filter itself has been tested and accredited.

In addition, we have also subjected these same components to RoHS testing to ensure that they do not contain any hazardous substances. The European RoHS directive (Restriction of Hazardous Substances) verifies, among other things, that a component contains no lead, mercury, cadmium, bisphenol B or phthalates.

Our components have passed these RoHS tests.

Finally, and this is unique enough to mention, not only are our components NSF® certified, but the Ultimate Star Filter® itself is NSF® certified.

The top and bottom tanks of our Star Water Filter® filtration systems are manufactured with identical volumes.

As a reminder, here are the trade names of our models:

• Model Mini Star 5.6 litres
• Model Big Star 8.5 litres
• Model Super Star 12.3 litres

As a result, if you fill the upper tank completely, you run the risk of an overflow. This is partly due to the position of the tap on the lower tank, which causes a certain volume of water to be stored below it. Secondly, because of the way the tanks fit together, with the upper tank fitting into the lower tank, creating a 2 cm high gap that cannot be filled with water.

Useful capacity (water filtered in the lower tank) of our models:

• Model Mini Star: 5 litres
• Model Big Star: 8 litres
• Model Super Star: 17.7 litres

Residual water in low tank below tap level:

• Model Mini Star: 1 litres
• Model Big Star: 1.2 litres
• Model Super star: 1.5 litres

Taking these figures into account, when filling your system, you should respect the following volumes:

For more detailed information, read our advice on use.

Our filters are high-performance and have been tested with a wide range of pollutants to ensure their effectiveness.

They are therefore capable of filtering most of the pollutants potentially present in your tap water: bacteria, viruses, drug residues, heavy metals, PFAS, pesticides, etc.

What about filtering water that is not tap water?

First of all, you need to proceed with caution and always use water that you know is safe to drink.

If, however, in a particular situation (an emergency or self-sufficiency situation, for example), you are obliged to filter water that is not mains water, a number of precautions need to be taken:

• Carry out preliminary tests to check that the water does not contain any pollutants that are not listed in our analyses and for which we have not carried out tests. Even if we know that our filter is capable of eliminating certain pollutants that have not been tested, we cannot guarantee its effectiveness on a particular pollutant if it has not been analysed.
• Precautions when handling: if your water only contains pollutants identified as being treated by our filter, and in normal concentration, you may consider filtering it. In this case, the water must not be used to prime your filters or clean your system, and must not be brought into contact with any other element of the filter to avoid pollution. The water should be poured directly into the upper tank, avoiding any overflow or splashes. Be careful not to touch the water with your hands, as contact with it could pollute your system.
• To prime your filters, soak them for 2 to 3 hours in clean water, or use a tap connected to the mains water supply. This is to avoid contamination of your filters.

If in doubt, contact us by telephone or via our contact form.

Premium Water Distribution SAS accepts no responsibility for any failure to observe these precautions.

What is fluoride?

Fluoride (or fluoride ion) is the ionic form of fluorine, which can be found in water in the form of salts.

Where does fluoride come from?

Fluoride occurs naturally in certain rocks. Its most abundant form is fluorite. The fluoride salts found in water come from the dissolution of fluorite from granite or sedimentary rocks.

What is its effect on health?

Fluoride is not particularly useful for human growth or development. However, it can help prevent tooth decay. This is why some manufacturers have added fluoride to toothpastes, and why some countries have resorted to water fluoridation.

On the other hand, excessive fluoride intake can cause a condition known as bone fluorosis. Fluoride weakens bone structure and can cause certain bones in the body to become brittle.

Fluoride in water around the world

Fluoride levels in drinking water can sometimes exceed recommended thresholds. This is particularly the case when groundwater comes from volcanic or mountainous areas.

At the beginning of the 21st century, around 378 million people worldwide were receiving artificially fluoridated water, the vast majority of them in the United States. Of these, almost 14 million people in Western Europe had access to artificially fluoridated water.

The effectiveness of activated carbon filters on fluoride

Activated carbon-based filters, even when supplemented by other filter media, are not very effective on fluoride. Only osmosis filters are able to retain it effectively.

Our Ultimate Star Filter® is no exception to the rule, and our tests have shown an efficiency of around 45%.

As a result, we are studying the design of a complementary filter, which will be effective on fluorides and other pollutants, to complement the main filter for use when the water to be filtered is particularly loaded with these components.

While we await the launch of these new filters, our Ultimate Star Filter® is compatible with Berkey® PF-2.

Nitrites and nitrates in water

Nitrites and nitrates in water are classified as nitrogen pollutants. Although they occur naturally in the environment, they are mainly introduced in significant quantities by human activity through agriculture, wastewater treatment, and industrial activities.

In addition, nitrites are used by the food industry as a preservative in processed meats. However, they also enter ecosystems through the natural process of organic matter degradation, such as plants or leaves. The presence of nitrites in water often indicates organic pollution, which may be due to the presence of urine or feces.

Nitrates are an essential nutrient for plant growth. Their excessive presence in water comes from livestock farming and intensive agriculture. Nitrogen fertilizers are broken down into nitrates by bacteria in the soil.

Risks associated with the presence of nitrites and nitrates in water

Nitrites are classified as probable carcinogens. They are found in high concentrations in processed meats and, in an acidic environment (such as the stomach), they form proven carcinogenic by-products. A study of more than 100,000 people found an increased risk of type 2 diabetes in people who consumed nitrites, including those found in processed meats.

This is why their content in drinking water is regulated. The same applies to nitrates, as they can be converted into nitrites.

Excessive concentrations of nitrates in water are also a proven source of pollution. They have a harmful effect on aquatic life, promoting the proliferation of harmful algae that reduce oxygen levels, but also on human health. They are responsible for various diseases, including certain forms of cancer.

The action of activated carbon filters on nitrites/nitrates

Activated carbon reduces nitrite and nitrate levels in water. However, it cannot reduce them completely on its own. Our Ultimate Star Filter® has been tested with an efficiency of around 40%. Analyses carried out on certain activated carbon filters that claim to reduce nitrates by more than 90% should be treated with caution. As things stand, this is simply impossible...

We provide real figures, but we are also working on the design of a complementary filter that will be effective against nitrites and nitrates, to be used in addition to our main filter.