ZeroWater makes two filter sizes. Here's how to find out which one you need.

<h2 id="two-filter-sizes">Two filter sizes</h2><p>ZeroWater makes two replacement filter sizes, and it&apos;s important to order the correct one for your pitcher:</p><ul><li><strong>Original ZeroWater filter&#xA0;</strong>&#x2014; standard filter, fits all original ZeroWater pitchers (most of them have the blue reservoir)</li><li><strong>Culligan with ZeroWater technology filter</strong> &#x2014; fits the new Culligan pitchers with drop in filters.</li></ul><p>These filters can not be used interchangeably.&#xA0;</p><h2 id="how-to-check-which-filter-you-need">How to check which filter you need</h2><p>The easiest way is to look at your existing filter. The model number is printed on the side of the filter itself, the original ZeroWater filters are noted as ZR-017. These are the filters that we have available.</p><p>Alternatively, check the bottom of your pitcher &#x2014; the model number of the pitcher is usually printed there, and the product listing on our website will confirm which filter it uses.</p><h2 id="where-to-buy-replacement-filters">Where to buy replacement filters</h2><p>Replacement filters are available at <a href="https://www.zerowaterfilter.com/products/replacement-filters?variant=50024084111688">zerowaterfilter.com</a>. Multi-packs offer better value if you go through filters frequently due to high local water TDS.</p><h2 id="not-sure">Not sure?</h2><p>If you&apos;re unsure which filter fits your pitcher, please <a href="https://www.zerowaterfilter.com/pages/contact">contact our customer service team</a> with your pitcher model number or an image of your pitcher and we&apos;ll confirm the right filter for you.</p>

Which replacement filter fits my ZeroWater pitcher?

Yes — ZeroWater removes virtually all dissolved minerals. Here's what that means for your health and your water quality.

<h2 id="yes-zerowater-removes-minerals">Yes, ZeroWater removes minerals</h2><p>ZeroWater&apos;s 5-stage ion exchange filter removes <strong>99&#x2013;100% of dissolved solids</strong> from your water, including naturally occurring minerals like calcium, magnesium, potassium, and sodium. This is why the TDS meter reads 000 after filtering &#x2014; virtually nothing dissolved remains.</p><h2 id="is-removing-minerals-harmful">Is removing minerals harmful?</h2><p>This is a common question. The short answer is: <strong>no, for most people</strong>.</p><p>While minerals in water can contribute to your daily intake, they represent a very small fraction of your total mineral consumption compared to food. Health organisations, including the World Health Organisation, acknowledge that drinking very low-mineral water is not harmful as part of a balanced diet.</p><p>If you have specific dietary concerns or health conditions, it&apos;s worth discussing with your GP or a nutritionist.</p><h2 id="why-remove-minerals-at-all">Why remove minerals at all?</h2><p>The same ion exchange process that removes beneficial minerals also removes harmful dissolved solids &#x2014; lead, chromium, nitrates, fluoride, pharmaceutical residues, and hundreds of other contaminants. ZeroWater removes them all, without distinction, giving you the purest possible filtered water.</p><h2 id="what-about-remineralisation">What about remineralisation?</h2><p>Some customers choose to add a remineralisation drop or electrolyte product to their filtered water. This is completely safe and simply comes down to personal preference &#x2014; it won&apos;t affect how well your filter works. A popular option is <strong>Third Wave Water</strong>, which is designed to restore minerals for taste or for specific brewing needs like coffee and espresso.</p>

Do ZeroWater filters remove minerals from water?

No — ZeroWater filters are for cold water only. Filtering hot water will damage the filter and may reduce its effectiveness.

<h2 id="cold-water-only">Cold water only</h2><p>ZeroWater filters are designed for <strong>cold tap water only</strong>. The maximum recommended water temperature is approximately <strong>30&#xB0;C</strong>. Do not use the filter with hot or boiling water.</p><h2 id="why-does-temperature-matter">Why does temperature matter?</h2><p>The ZeroWater filter uses an ion exchange resin to remove dissolved solids. This resin is sensitive to heat &#x2014; high temperatures can cause the resin to release previously captured ions back into the water, defeating the purpose of filtering. It can also physically damage the filter structure.</p><h2 id="what-about-warm-tap-water">What about warm tap water?</h2><p>Slightly warm water (e.g. if your tap runs warm in summer) is unlikely to cause damage. However, for best results, always use cold tap water and check that your TDS reading stays at 000&#x2013;005 after filtering.</p><h2 id="making-hot-drinks-with-filtered-water">Making hot drinks with filtered water</h2><p>The correct approach is to filter cold tap water first, then boil it separately in a kettle. This gives you the benefits of ZeroWater filtration for your tea, coffee, or cooking without damaging the filter.</p>

Can I filter hot or warm water with ZeroWater?

ZeroWater is designed for tap water only. Here's what works, what doesn't, and why.

<h2 id="use-tap-water-only">Use tap water only</h2><p>ZeroWater filters are designed to filter <strong>cold tap water (mains water)</strong>. This is the only water source for which the filters are tested, certified, and rated.</p><h2 id="what-not-to-filter">What not to filter</h2><ul><li><strong>Hot or warm water:</strong> Do not use water above approximately 30&#xB0;C. Heat can damage the ion exchange resin inside the filter. See <a href="/en-GB/Can-I-filter-hot-or-warm-water-with-ZeroWater-7747351">Can I filter hot or warm water?</a></li><li><strong>Well water or borehole water:</strong> Not recommended. Untreated well water may contain bacteria, viruses, and organic compounds that ZeroWater&apos;s ion exchange filter is not designed to handle.</li><li><strong>Rainwater or greywater:</strong> Not suitable. These sources can contain microorganisms and pollutants beyond the filter&apos;s scope.</li><li><strong>Bottled mineral water or sparkling water:</strong> You can filter these, but there&apos;s no practical benefit. The filter will simply remove the minerals, reducing the TDS to 000.</li><li><strong>Saltwater or highly contaminated water:</strong> Not suitable. Extremely high TDS water will exhaust the filter very quickly and the filter is not designed for desalination.</li></ul><h2 id="pre-filtered-or-softened-water">Pre-filtered or softened water</h2><p>ZeroWater works fine on water that has already passed through a softener or another filter. In fact, starting with lower-TDS water means your ZeroWater filter will last longer.</p>

Can I filter water other than tap water with ZeroWater?

Yes — all ZeroWater pitchers, reservoirs, and filters are made from BPA- and BPS-free materials.

<h2 id="bpa--and-bps-free-across-the-range">BPA- and BPS-free across the range</h2><p>All ZeroWater pitchers, upper reservoirs, lids, and filters are manufactured using <strong>BPA-free and BPS-free materials</strong>. This applies to the entire product range sold on zerowaterfilter.com.</p><h2 id="what-are-bpa-and-bps">What are BPA and BPS?</h2><p>Bisphenol A (BPA) and Bisphenol S (BPS) are chemicals used in some plastics manufacturing that can leach into food and water. They have been linked to hormonal disruption and other health concerns, particularly in infants and children. Many countries have restricted or banned BPA and BPS in food-contact plastics.</p><h2 id="what-plastics-does-zerowater-use">What plastics does ZeroWater use?</h2><p>ZeroWater products are made from food-grade plastics including polypropylene (PP) and ABS, none of which contain BPA or BPS, and are safe for prolonged contact with drinking water.</p><h2 id="further-certifications">Further certifications</h2><p>ZeroWater filters are NSF/ANSI certified for performance. For full certification details, see <a href="/en-GB/Is-ZeroWater-certified-Performance-results-and-data-sheets-7747354">Is ZeroWater certified?</a></p>

Are ZeroWater products BPA- and BPS-free?

ZeroWater filters are not designed for Culligan systems and cannot be used as a direct replacement.

<h2 id="compatibility-with-culligan">Compatibility with Culligan</h2><p>ZeroWater filters are designed specifically for ZeroWater pitchers and dispensers. They are <strong>not compatible with Culligan filtration systems</strong> and cannot be used as a drop-in replacement for Culligan filters.</p><p>Culligan systems use their own proprietary filter cartridges. Attempting to install a ZeroWater filter in a Culligan system is not possible due to different dimensions and connection mechanisms.</p><h2 id="looking-to-switch-to-zerowater">Looking to switch to ZeroWater?</h2><p>If you&apos;re considering switching from a Culligan pitcher to a ZeroWater pitcher, you would need to purchase a ZeroWater pitcher as well as the ZeroWater filters. The ZeroWater pitchers are available on <a href="https://zerowaterfilter.com">zerowaterfilter.com</a>.</p><h2 id="questions">Questions?</h2><p>If you&apos;re unsure about compatibility with a different system, please <a href="mailto:service@zerowaterfilter.com">contact our customer service team</a>.</p>

Are ZeroWater filters compatible with Culligan systems?

Store unused filters in a cool, dry place away from direct sunlight. Here's everything you need to know.

<h2 id="storing-unused-filters">Storing unused filters</h2><p>Unused ZeroWater filters in their original sealed packaging can be stored safely for an extended period &#x2014; <strong>up to 2 years</strong> if kept in the right conditions.</p><h2 id="storage-conditions">Storage conditions</h2><ul><li><strong>Cool and dry:</strong> Store at room temperature, away from heat sources and moisture.</li><li><strong>Out of direct sunlight:</strong> UV light can degrade the packaging and potentially the filter media over time.</li><li><strong>In original packaging:</strong> Keep the filter in its sealed bag until you&apos;re ready to install it. The bag protects the filter media from drying out and from contamination.</li></ul><h2 id="can-i-store-a-filter-thats-already-been-used">Can I store a filter that&apos;s already been used?</h2><p>Once a filter has been installed and used, it should not be stored dry for long periods &#x2014; the ion exchange resin needs to stay moist to function correctly. If you remove an in-use filter (for example, when travelling), keep it in a clean sealed bag in the fridge and reinstall it within a few days.</p><p>Do not freeze a used filter &#x2014; this can damage the resin.</p><h2 id="expired-or-old-filters">Expired or old filters</h2><p>If you&apos;re unsure whether an old filter is still good, install it and test your filtered water with the TDS meter. If it reads 000&#x2013;005, it&apos;s working fine. If it reads 006 or higher from the first use, the filter may have degraded.</p>

How should I store my ZeroWater replacement filters?

Like all water filters, ZeroWater filters can harbour bacteria if not used correctly. Here's what you need to know.

<h2 id="can-bacteria-grow-in-the-filter">Can bacteria grow in the filter?</h2><p>ZeroWater filters are not designed to remove bacteria or viruses &#x2014; they are designed to remove dissolved inorganic solids. In theory, bacteria present in tap water could pass through the filter, and in some conditions, bacteria could colonise the filter media if the filter is used beyond its lifespan or the pitcher is not kept clean.</p><h2 id="how-to-minimise-the-risk">How to minimise the risk</h2><ul><li><strong>Replace your filter on time.</strong> Replace when your TDS reading reaches 006. An overloaded filter is more susceptible to bacterial growth.</li><li><strong>Store the pitcher in the fridge.</strong> Cold temperatures significantly inhibit bacterial growth. Filtered water should be consumed within 2&#x2013;3 days if stored at room temperature, or up to a week if refrigerated.</li><li><strong>Clean the pitcher regularly.</strong> Wash the pitcher body and reservoir at least monthly. See <a href="/en-GB/How-do-I-clean-my-ZeroWater-pitcher-7747327">How do I clean my ZeroWater pitcher?</a></li><li><strong>Don&apos;t leave water sitting too long.</strong> Don&apos;t fill the pitcher and leave it unused for extended periods.</li></ul><h2 id="is-tap-water-in-the-ukeu-safe-from-bacteria">Is tap water in the UK/EU safe from bacteria?</h2><p>Yes &#x2014; tap water in the UK and EU is treated to be microbiologically safe before it reaches your tap. Bacterial contamination in tap water is extremely rare. ZeroWater&apos;s filtration removes the chemical and dissolved solid concerns; the microbiological safety of European tap water is handled at the treatment level.</p><h2 id="questions">Questions?</h2><p>If you have specific concerns about water quality in your area, your local water authority can provide water quality reports. For questions about your ZeroWater product, <a href="https://www.zerowaterfilter.com/pages/contact">contact our team</a>.</p>

Can bacteria grow inside a ZeroWater filter?

ZeroWater's 5-stage filter is certified to reduce PFOA, PFOS, lead, chromium, mercury and chlorine, plus a wide range of other contaminants.

<h2 id="what-we-remove">What we remove</h2><p>ZeroWater&apos;s 5-stage ion-exchange filter is independently certified by IAPMO to reduce <strong>PFOA, PFOS, lead, chromium, mercury and chlorine</strong> &#x2014; and lab testing shows it also significantly reduces a wide range of other contaminants, including antimony, arsenic, barium, cadmium, copper, iron, manganese, selenium, silver, thallium, zinc, cyanide, fluoride, asbestos, nitrate and nitrite.</p><h2 id="how-it-compares">How it compares</h2><p>In independent lab tests (following NSF/ANSI standards), ZeroWater consistently outperformed a leading two-stage filter &#x2014; for example, reducing chromium 6 by 99% versus around 30% for the competitor, and lead by 99% versus roughly 80&#x2013;86%.</p><h2 id="full-performance-data">Full performance data</h2><p>For the complete breakdown of test results and certifications, visit our <a href="https://www.zerowaterfilter.com/pages/performance-results">Performance Results page</a>.</p>

What substances does the ZeroWater filter remove?

Your filter doesn't need to stay in water constantly — here's how to store it if you won't use it for a few days.

<h2 id="storing-an-opened-filter">Storing an opened filter</h2><p>Your ZeroWater filter doesn&apos;t need to stay in water constantly. If you&apos;re not going to use it for a few days, we recommend storing it in an airtight bag or container in the fridge to keep it fresh. Never freeze a used filter &#x2014; this can damage the resin.</p><h2 id="how-long-can-i-store-it">How long can I store it?</h2><p>Please note: we recommend not storing or using an opened filter for longer than <strong>3 months</strong> after opening.</p><h2 id="more-information">More information</h2><p>For how to store an unopened filter, see <a href="/en-GB/How-should-I-store-my-ZeroWater-replacement-filters-7747349">How should I store my ZeroWater replacement filters?</a>.</p>

Can I store my filter after opening?

Some new filters can release fine carbon particles at first — this is safe and easy to fix.

<h2 id="why-does-this-happen">Why does this happen?</h2><p>Some brand new filters can let fine carbon particles into the water due to the way they&apos;ve settled during manufacturing or transport. This is completely normal and safe.</p><h2 id="how-to-fix-it">How to fix it</h2><p>Simply flush the system &#x2014; run water through the filter a few times &#x2014; until the water runs clear.</p><h2 id="related">Related</h2><p>If you&apos;re instead seeing specks in your upper reservoir rather than discoloured water, see <a href="/en-GB/Why-are-there-black-or-brown-specks-in-my-water-tank-7747344">Why are there black or brown specks in my water tank?</a></p>

The water coming out of my filter is black or gray

An overview of the BPA-free materials used in ZeroWater filters, pitchers and dispensers.

<h2 id="what-our-products-are-made-of">What our products are made of</h2><p>ZeroWater filters are made of <strong>BPA- and BPS-free polypropylene</strong>.</p><p>ZeroWater pitchers and water dispensers are made of <strong>BPA-free polypropylene</strong> and <strong>ABS (acrylonitrile butadiene styrene)</strong>.</p><h2 id="more-information">More information</h2><p>For more on our BPA-free materials, see <a href="/en-GB/Are-ZeroWater-products-BPA-free-7747338">Are ZeroWater products BPA-free?</a></p>

What materials are ZeroWater products made of?

Yes — ZeroWater filtered water works well in kettles, coffee makers, and espresso machines, and can help reduce limescale build-up over time.

<p>Yes &#x2014; ZeroWater filtered water works well in kettles, coffee makers, and espresso machines. Because it removes virtually all dissolved solids, it can also help reduce limescale build-up in your appliance over time.</p>
<p>For espresso machines in particular, some users prefer to add a small amount of minerals back in for flavour and extraction. Products like Third Wave Water offer mineral packets designed specifically for this &#x2014; you add them to your filtered water to restore a balanced mineral profile suited to espresso brewing. See &quot;Do ZeroWater filters remove minerals from water?&quot; for more on that.</p>

Can I use ZeroWater filtered water in a kettle, coffee maker, or espresso machine?

Limescale comes from dissolved minerals like calcium and magnesium — here's how ZeroWater's filter deals with it, and how to remineralise for coffee.

<p>Yes. Limescale is caused by dissolved minerals such as calcium and magnesium, and ZeroWater&#x2019;s 5-stage ion exchange filter removes these along with other dissolved solids.</p>
<p>Because ZeroWater removes virtually all dissolved minerals from your water, it also removes the minerals that cause limescale build-up in kettles, coffee machines, and other appliances.</p>
<h3 id="brewing-coffee-with-zerowater">Brewing coffee with ZeroWater</h3>
<p>If you brew coffee, near-zero TDS water is actually the ideal starting point &#x2014; but coffee does need some minerals to extract properly. That&#x2019;s where <a href="https://thirdwavewater.eu/">Third Wave Water</a> comes in: small mineral sachets designed to remineralise ultra-pure water like ZeroWater&#x2019;s to the exact profile specialty coffee needs. Simply fill your ZeroWater jug, pour the filtered water into a bottle, and add one sachet of your chosen Third Wave Water profile (light roast, medium roast, dark roast, espresso, cold brew, or low acid) for more consistent extraction and cleaner flavour.</p>
<p>For the full explanation of what ZeroWater removes and why, see our article on whether ZeroWater filters remove minerals from water.</p>

Does ZeroWater remove limescale?

Yes — ZeroWater removes the calcium and magnesium that cause water hardness, giving you soft, mineral-free water.

<p>Yes &#x2014; because ZeroWater removes the calcium and magnesium responsible for water hardness, filtering hard tap water through ZeroWater effectively gives you soft, mineral-free water.</p>
<p>Keep in mind that the harder your tap water, the higher its starting TDS (total dissolved solids) &#x2014; and the more dissolved solids your filter has to remove, the faster it will use up its capacity. So if you have hard water, expect your filter to need replacing sooner than it would with softer tap water.</p>
<p>For the full explanation of what&apos;s removed and why, see &quot;Do ZeroWater filters remove minerals from water?&quot;.</p>

Most asked questions