Why does my TDS meter show 000 or 0000?Updated 2 months ago

A reading of 000 is a good thing

ZeroWater is the only water filter brand that consistently removes virtually all dissolved solids (TDS) from your tap water. When your TDS meter shows 000 or 0000, it means your filter is removing 99–100% of dissolved solids — exactly as it should.

The free TDS meter included with every ZeroWater pitcher lets you monitor filter performance and know exactly when to replace your filter.

What if 000 seems wrong?

If you've been using your filter for a long time and it suddenly shows 000 again, the most likely explanation is that the meter needs recalibrating or the battery is low. Try the following:

• Test a glass of unfiltered tap water — it should read well above 000 (most tap water reads between 100–400). If tap water also reads 000, your meter battery may be dead or the meter needs checking.
• Rinse the meter probes with filtered water and dry them before testing.
• Check if the HOLD button is not activated by pushing it once and retesting
• Not seeing any numbers after turning on the meter, check the battery: remove the cap at the bottom of the meter and replace the battery if needed (LR44 button cell).

When should I replace my filter?

Replace your filter when the TDS meter reads 006 or higher on your filtered water. A reading of 000–005 means your filter is still working well.

My tap water already reads 000 — is that normal?

This is very rare but possible if you live somewhere with exceptionally soft water. In that case, filtered water will also read 000 — your filter is still working, there's just very little to remove. You can confirm by testing with a known mineral water.

Still have questions?

If your TDS meter is behaving unexpectedly, our customer service team is happy to help — contact us here.