Your ZeroWater pitcher or dispenser comes with a TDS meter for a reason: it tells you exactly when the filter is used up, so you never have to guess. Here is how to read it, how long a filter usually lasts in your area, and how to swap it in a few minutes.
The one rule: replace the filter when the meter reads 006 or higher
Test your filtered water with the included ZeroWater TDS meter. ZeroWater recommends replacing the filter when the meter reads 006 or higher, and recommends not letting the reading go past that point. A fresh filter typically reads 000.
New to TDS? Here is what TDS means and why it affects the taste of your water.
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How long a filter lasts depends on your tap water TDS
Total dissolved solids (TDS) are organic and inorganic materials, such as metals, minerals, salts, and ions dissolved in water. The more dissolved solids in your tap water, the faster a filter reaches its limit. To estimate your filter life, test your unfiltered tap water with the meter and find your range:
| Tap water TDS | Expected gallons per filter |
|---|---|
| 002 to 050 | 40 gallons or more |
| 051 to 200 | 25 to 40 gallons |
| 201 to 300 | 15 to 25 gallons |
| 301 to 400 | 8 to 15 gallons |
| 401 and above | 8 gallons or less |
Most tap water in the U.S. falls in the 051 to 200 range. Your actual results depend on how much water your household filters and on your local water. If your tap water reads 401 or higher, contact ZeroWater support and they can help you find the right approach.
Other signs it may be time for a new filter
The meter is the most reliable check, but you may also notice a change in taste or smell. A sour or lemon-like taste is a common sign the filter is used up. Here is why ZeroWater can taste like lemon and what to do about it.
What to do if the meter reads high right after a change
- Make sure you filled the pitcher with cold tap water.
- Check that the filter is seated firmly in the pitcher.
- Rinse the pitcher and reservoir and filter again.
- Retest. If the meter still reads 006 or higher on a new filter, contact support.
How to replace your ZeroWater filter in 5 steps
- Take the pitcher or dispenser apart so you can reach the old filter.
- Remove the old filter.
- Take the blue cap off the new filter.
- Twist the new filter into place.
- Fill the reservoir with cold tap water, then test the filtered water with your meter.
ZeroWater filters do not need to be soaked, flushed, or otherwise prepped before use. You may see harmless condensation inside the bag or lid. For step-by-step help with your specific model, see the FAQ.
Never run out: set up auto-delivery
Because filter life depends on your water and your household, many owners prefer to have replacements arrive on a schedule. See auto-delivery options or shop replacement filters in packs of 2 to 12.
Frequently asked questions
How do I know when to change my ZeroWater filter?
Replace it when your TDS meter reads 006 or higher on filtered water.
Does a higher tap water TDS shorten filter life?
Yes. The more dissolved solids in your tap water, the fewer gallons each filter will produce. See the table above for typical ranges.
Can I tell by taste alone?
A change in taste or smell can be a sign, but the meter is the most reliable way to know.
Do I need to soak or flush a new filter?
No. ZeroWater filters do not need to be soaked, flushed, or prepped before use.
Where can I find replacement filters?
Shop ZeroWater replacement filters online or find them at participating retailers.
