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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.
| Categories of polluants | |
|---|---|
| Microbiology | Heavy metals |
| Pesticides / Herbicides | Heavy and light solvents |
| Chlorine and derivatives | Medicinal residues |
| PFAS | Plastic derivatives |
| Hormones | Microplastics |
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:
| Ultimate Star Filter® flow rate | |
|---|---|
| New filter | 12 litres / hour |
| After 750 litres | 8 litres / hour |
| After 1500 litres | 5.6 litres / hour |
| After 2500 litres | 4.2 litres / hour |
| At 3000 litres | 3 litres / hour |
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.
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A gravity filter, as the name suggests, is a filter that uses gravity to ‘push’ the water through the filter media.
There are a number of advantages to this filtration principle: apart from its ease of use and maintenance, its main advantage is that the system is completely autonomous. You don't need electricity or water pressure to operate. All you have to do is fill the upper tank, and the water flows through the filter into the lower tank without any external action. This ensures ease of use and maintenance, and complete autonomy, even when you don't have access to a power source or mains water. So it's perfectly usable, even in an emergency.
Another advantage is that the low flow rate of this filter means that the water (and its pollutants) are in prolonged contact with the different layers of the filter, resulting in enhanced efficiency.
For more information, read our page on how a gravity-fed water filtration system works in detail.
This is a fairly recurrent question, and many people tell us how surprised they are when they read their filtered water readings taken with a TDS (or conductivity) meter.
Let's start by being very clear : a TDS reader cannot be used to check the quality of water, and even less to tell whether or not there are pollutants in the water. That's absolutely not what this device is for. It's like using a screwdriver to drive in a nail or a hammer to fix a screw...
What is a TDS reader used for?
TDS stands for Total Dissolved Solids and is used to measure solids dissolved in water in ionic form. These can be salts, minerals or metals. This device actually measures the conductivity of the water. The more solids dissolved in water, the more electrically conductive it is.
The readers, or TDS meters, therefore indicate a measurement that corresponds to the conductivity of the water, and this measurement is expressed in microsiemens or, more generally, in PPM (Parts Per Million). This unit corresponds to the number of solid particles per million particles of water. In other words, a value of 50 ppm means that in one million particles of water, there are 50 dissolved ions.
Can the value measured by a TDS meter indicate water quality?
Assuming that water with a value of 0 ppm is pure and free from pollutants is not true. The TDS meter only measures the number of ions dissolved in the water. However, most pollutants, whether pesticides, substances with endocrine effects or drug residues, are generally not ions. What we can say in this case is that the water is free of mineral salts, but it may be highly charged with various pollutants.
On the other hand, water with a high value in no way means that it is polluted. It just means that it contains a significant number of mineral salts or metals.
The value indicated by a TDS reader is therefore absolutely no indication of whether or not the water is polluted. Do not use this device for that purpose. The only way to find out is to have it analysed in a specialised laboratory, where samples are taken very precisely and according to a specific protocol.
The concept of water potability is based on the absence of substances that are harmful to health. The criteria associated with potability are laid down by health safety agencies and depend on the country concerned.
Broadly speaking, they take into account physicochemical, organoleptic and microbiological parameters and the quantity of undesirable substances.
The maximum quantities or tolerated thresholds of these undesirable substances are defined according to criteria based on current scientific knowledge. However, these studies are often incomplete or do not take into account new substances discovered at a late stage. Examples include the recent water scandals involving PFAS, TFA and vinyl chloride.
New pollutants are discovered regularly, and not only do our drinking water treatment systems become obsolete over time, but they are often ineffective against a growing number of pollutants that concentrate in our groundwater.
And even if thresholds are set, below which each pollutant is not supposed to be toxic or dangerous, we know on the one hand that there is a phenomenon of bioaccumulation in the body, and on the other, that the cocktail effects of these substances are poorly known and difficult to identify, although deleterious.
As for bottled water, we now know that not only is it polluted, but that its standards are much more relaxed than those for tap water, and that controls are less rigorous.
The only way to avoid these risks is to filter and depollute tap water, even if it is still ‘drinkable’ and partly depolluted. Adopt the right approach and opt for a Star Water Filter® gravity-fed water filtration system.
You can find out more on this subject on our ‘Why filter your drinking water’ page.
There are a number of situations in which Ultimate Star Filter® filters need to be stored.
New filters
New filters, unopened and in their original packaging, can be kept indefinitely provided they are stored in a dry, dark and, above all, odour-free place. Activated carbon has the property of absorbing odours and the filter can then concentrate these fragrances and release them when they are put back into service.
Filters already in use
It all depends on the length of absence.
For an absence of 3 days or less, simply leave them in place in the upper tank.
For an absence of more than 3 days and less than or equal to 7 days, you should dismantle them and store them in an airtight bag (like a freezer bag) in the fridge, without freezing them.
For an absence of more than 7 days, you need to dismantle them, dry them by holding them in a vertical position, with the threaded stem at the bottom, and leave them to dry for at least 2 or 3 days. Once completely dry, you can store them in a cool, dry, odour-free place, ideally in a paper bag.
If you're away for more than 3 days, you'll need to put the filters back into service.
For more information, see our page on how to use and maintain your Star Water Filter® gravity-feed water filtration system.
Like any appliance designed to receive and store food for human consumption, it needs to be cleaned from time to time. The main maintenance of Star Water Filter® systems consists of regular cleaning of the components that make up the system: tanks, tap, lid and filters.
These operations should be carried out every 1 to 3 months, depending on the type of water used and its hardness.
For the tanks and lid, simply use soapy water and/or water containing a little vinegar if there is a tendency for limescale to build up. Warning: the filters must never be brought into contact with any product whatsoever.
For the tap: apart from regular external cleaning, if the flow rate decreases significantly, we recommend that you dismantle the tap and treat it with household vinegar to remove the limescale.
As for the filters, gently rubbing the outside surface with a sponge under a trickle of water will remove any activated carbon pores that may be blocked by limescale or sediment. This operation should be carried out a few times during the life of the filter if the flow rate decreases significantly.
These are the only maintenance operations to be carried out on Star Water Filter® systems.
More details on these operations on the maintenance page for your filtration system.
Whether you are installing your system for the first time, replacing your filters, or reassembling your system after storing your filters while you are away, you need to prime your filters before installing them in the upper tank.
Your filters are made up of several filter media, including activated carbon with tiny pores and micro-channels. These micro-channels are originally filled with air. Because filters work solely by gravity, the pressure allowing water to pass through the filter is very low. If air remains trapped inside the filter, the water will not be able to push it out and will be blocked, resulting in a very slow flow rate, or even none at all.
It is therefore necessary to prime the filter before installation.
Priming consists of pushing water with a certain pressure inside the filter to expel the air. This is done using a silicone nipple or a silicone priming washer.
This operation is described in detail on our Star Water Filter® system start-up page.
Installing your Star Water Filter® gravity filtration system is very simple and intuitive.
It consists of fitting the tap to the lower tank, the filters to the upper tank and assembling the two tanks.
However, to make assembly as simple and straightforward as possible, and in accordance with the instructions provided, please refer to our page on assembling your filtration system.
To compare standard flow rates with your own, you can check the flow rates of Ultimate Star Water® water filters.
However, these flow rates are theoretical and depend on several factors:
- Age of your filters: the more a filter is used and the closer it gets to the end of its service life, the more the flow rate will tend to slow down. This is perfectly normal, as the micro-channels in the filter will tend to become blocked over time due to limescale or simply sediment in the water.
- Water hardness: the harder the water, i.e. the more limescale it contains, the more likely it is that the filter will quickly become clogged due to the obstruction of its outer pores. It will then need to be cleaned and primed.
- Quality of priming: the way in which filters are primed, whether at start-up, when a new filter is installed, or after long storage, will have a significant influence on filtration speed. The aim of this operation is to expel the air contained in the pores and micro-channels of the filter element so that the water can pass through. In the event of poor priming, a filter may simply not let any water through at all, or at least substantially slow down the flow rate.
In any case, if you notice excessive slowness, clean your filters and then prime them.
Another reason for abnormal slowness may be the lack of air passage between the two tanks. For the water to fill the lower tank, the air in it must be able to escape. However, it can happen that the two tanks fit together so well that there is no air passage between them, a phenomenon that can be aggravated if water is present at this point and acts as a watertight seal. If this is the case, the small stainless steel clip supplied should be placed between the two tanks, to create a local gap between the two tanks, allowing air to pass through.
If, despite all this advice, you still can't solve your problem, don't hesitate to contact us by phone or via our contact form.
Yes, that's normal!
Your filtration system works by gravity. In other words, it's the pressure on the filter, linked to the height of the water column in the upper tank, that ‘pushes’ the water through the filter. The lower the water level in the tank, the lower the pressure, and there comes a time when it is no longer sufficient to ‘push’ the water through the filter.
What's more, the bottom of the filter is under more pressure than the top, since it is always submerged, and tends to clog up more as a result of limescale or sediment in the water.
However, this has no effect on the operation of your filter. This residual water is mixed regularly with the refill water that you bring in regularly (see this topic on the refill routine) and is filtered again during the next cycle.
As long as the residual water in your top tank does not exceed 5 cm, there's no need to worry. However, if this level tends to increase or filtration becomes very slow, you will probably need to clean your filter.
Is your system leaking? Don't panic, we'll help you solve the problem.
First of all, you need to identify where the leak is coming from. Water can only flow out of your system through the tap or between the two tanks.
Leak at the tap
In most cases, the leak is at the level of the washers, because the seal is not properly made. Check that there is a washer on each side of the tank. If a washer is missing or not correctly positioned, this could cause a leak. If the washers are present and correctly positioned, check that the nut holding the two seals and the tap is tight. This should be done by hand, or with an open-ended spanner, without forcing, so as to ensure a watertight seal, without damaging the seals or the tank itself.
More rarely, the leak may come from the tap itself.
If you find that drops are dripping from the tap itself, the leak may be due to a deposit of limescale that has built up inside and is preventing the internal seal from sealing properly. In this case, dismantle your tap, open it and fill it with white vinegar, leaving it in a position that allows the vinegar to remain inside. Leave the vinegar to work for a few hours, rinse and refit.
Level taps
If you have a level tap and the leak is coming from the lower junction between the glass tube and the metal part of the tap, it may be due to a faulty positioning or tightening of the silicone seal between the glass tube and the rest of the tap.
In this case, start by trying to tighten the top ring, which will compress the glass tube against the seal. If you can't do this by hand, use pliers and protect the ring with a cloth or sheet of paper to avoid damaging it. If this doesn't solve the problem, the silicone seal at the base of the glass tube may be incorrectly positioned.
Unscrew the top ring at the top of the tap that holds the glass tube in place. First by hand, and if you are unable to do so, with pliers, protecting the ring as indicated above. Once you have removed the ring, remove the glass tube. You'll see a silicone seal at the bottom of the top of the tap. Check that it is in the correct position, otherwise replace it correctly. Reposition the glass tube and tighten the ring correctly to compress the glass tube over the seal.
If all these solutions do not solve your problem, contact our customer service team who will be able to help you.
Leak between the two tanks
Your Star Water Filter® water filtration system works by gravity. This means that the water passes from the upper tank to the lower tank through the filters by being pushed through by gravity. There is no seal between the two tanks, otherwise the system would not work. This means that if you fill your upper tank when your lower tank is not empty, the water will overflow and pass between the two tanks. You should only fill your upper tank when your lower tank is empty.
For more advice on how to use your Star Water Filter® water filtration system, see the advice for use page.
Your lower tank is filled with filtered water, but despite this, the water from your tap flows very slowly.
There are two possible reasons for this:
Your tap is blocked
This can happen if you have very hard water and limescale has gradually built up in the tap pipe. In this case, follow our maintenance guide, which contains useful information on this subject.
Air cannot pass between the two tanks
When water flows from the lower tank through the tap, the same volume of air must enter the tank for the flow to occur. In some cases, the two tanks fit together so perfectly that no air enters the lower tank. This can be exacerbated if there is water between the two tanks, acting as a seal.
In this case, if you haven't already done so, simply slide the metal clip between the two tanks so that a gap is created and air can pass through.
If you encounter any difficulties despite these tips, don't hesitate to contact us by telephone or via our contact form.
Under normal circumstances, filtration takes place at a constant speed and fairly quickly.
You can check the flow rate of the Ultimate Star Filter® to see if your filtration time is correct.
In some cases, filtration may start, then stop or slow down considerably when there is still a lot of water in the top tank.
There are three main reasons for this
Lack of maintenance
Regular maintenance of your filters is necessary to remove any limescale or sediment deposits that may clog the outer pores of the filter. Read the maintenance instructions to find out how to clean your filters.
Faulty priming
When new filters are installed, or when they are cleaned or put back into service after a prolonged absence, they must be primed. Without this operation, your filters will not work properly. See our instructions on priming filters.
End of filter life
The closer you get to the end of the filter's life, the more the flow rate will tend to decrease, due to saturation of the filter and its clogging by limescale or natural sediments in the water.
The fact that some residual water remains in the upper tank after filtration is complete is not the same problem - it's a normal phenomenon.
When you receive your parcel, start by checking that you have all the items corresponding to your order by consulting the delivery note inside the parcel. If you forget or make a mistake, contact us immediately by telephone or via the contact form so that we can check and correct the problem as soon as possible.
Your parcel always contains a delivery note and an invoice.
Assembly, start-up, maintenance instructions and advice on using your Star Water Filter® water filtration system are available on our website.
When it leaves our warehouse, your parcel has left in perfect condition, but when you open it you notice that one item is damaged.
Despite all the care and precautions we take when preparing your parcel, you may find that an item is damaged when you open it.
Don't worry, we'll help you resolve the problem. In this case, please contact our customer service department by telephone or via our contact form, specifying the problem and enclosing a photo.
We are here to help you and we will resolve your problem as quickly as possible.
Please note: if you notice that the parcel itself is damaged and that the problem therefore stems from transport, you must make reservations as indicated in our delivery conditions. If no reservations are made, we will have no recourse against the carrier and will not be held liable.
For further information, please also refer to the section on damaged packages on receipt.
Your parcel has been delivered and you notice that it is damaged. The box is deformed, punctured or seems to have been damaged.
In this case, whether the delivery is to a relay point or a home delivery service, you must open the parcel in front of the shopkeeper/delivery person. If you notice the slightest damage, you must make a note of it on the delivery note before signing it. Don't hesitate to take photos to keep proof.
Then contact our customer service department by telephone using our contact form, and we will help you to replace the damaged product(s),
If the entire contents of your parcel are damaged, you must refuse the parcel.
DO NOT ATTEMPT TO INSTALL YOUR SYSTEM WITHOUT FIRST READING THE FOLLOWING RECOMMENDATIONS.
Installation, start-up, maintenance and operating instructions for your Star Water Filter® water filtration system are available on our website. They are essential for correctly assembling and commissioning your system. They also contain valuable information on the care and maintenance of your water filter.
Fitting your system and putting it into service without familiarising yourself with the information contained in these instructions may cause damage that will be detrimental to the smooth operation of your filtration system.
If you have any problems understanding or need advice, please do not hesitate to contact us by telephone or via our contact form. We will be delighted to help you.
When you confirm an order on the Star Water Filter® site by making payment, an order confirmation email is sent to you automatically and immediately. For various reasons, you may not receive this email.
Here are a few tips to help you identify the reason:
- Check your spam folder to see if it has been flagged as such by your e-mail provider. If this is the case, retrieve it and take the opportunity to declare our email address for this delivery as acceptable so that this problem cannot occur again.
- You may have made a typing error when entering your e-mail address in your customer account. If you are still logged in to your account, please check the address you have entered and amend it if necessary. Contact us by telephone or via our contact form so that we can send you the e-mail again.
- If you are unable to connect to your account because you cannot find the e-mail address you entered, contact us by telephone or via the contact form so that we can change the e-mail address for you and send you your order confirmation e-mail.
If none of these checks can explain why you have not received your order confirmation e-mail, please contact us by telephone or via the contact form and we will get back to you as soon as possible.
On the Star Water Filter® site, you can pay either by credit card via Crédit Agricole or PayPal, or via your PayPal account, or by cheque (for France) or bank transfer.
If you encounter a problem when paying for your order online, here's what you need to do:
Payment by cheque or by bank transfer:
In this case, you can contact us by telephone or via the contact form, stating your name and the nature of the problem you are experiencing so that we can solve your problem.
PayPal payment:
In the case of a PayPal payment, whether by credit card or via your account, you should contact PayPal customer service. We cannot intervene directly in problems related to their payment platform.
For any other problem, you can contact us by telephone or via the contact form.
You've placed an order and would like to change its content or delivery address, for example.
Depending on the status of the order, some things can still be changed. However, if your order has already been prepared or handed over to the carrier, we will no longer be able to change anything.
Before 1pm, some of these changes are still possible. After this time, it will no longer be possible, as your order will have been prepared or dispatched.
In all cases, please contact us as soon as possible by telephone or via our contact form.
Orders are validated and prepared every day (except weekends) and cannot be changed after 1pm.
If you place your order in the afternoon, it can be cancelled before dispatch until 1pm the following day. If you place your order in the morning, it must be cancelled before 1pm.
If your order has already been dispatched, it can no longer be cancelled and you will have to submit a cancellation request. You will be responsible for the cost of returning the parcel.
In all cases, you must contact our customer service department using our contact form, indicating your order reference.
You will receive a reply very quickly, and your refund will be processed within a few days.
First of all, you must contact our customer service department to inform us of your withdrawal request.
We need to validate that your request meets the eligibility requirements for a return. See our returns policy for more information.
Once these conditions have been validated and our agreement given, you must return your products within 5 days.
The return costs are at the customer's expense. The initial shipping costs remain at the customer's expense for all shipments outside the EU.
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