What's the ideal borate level?

30–50 ppm. Below 30 you get little benefit; above ~50 there's no added value.

Do borates replace chlorine?

No — borates suppress algae but don't sanitize. You still need chlorine, just possibly a touch less.

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Pool Borate Calculator

Borates fight algae and steady your pH. Enter your current level and we'll give you the boric acid dose to reach the 30–50 ppm sweet spot.

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Balance your whole pool at once →Enter all your readings on one screen and get an ordered dosing plan — the full Water Report.

How to use it

Test your borate level (a borate strip).
Enter it, your target (50 ppm is typical), and your volume.
Add boric acid, brush to dissolve, and re-test after a day of circulation.

Why add borates?

Borates (30–50 ppm) act as a secondary buffer that helps lock pH in place, and they suppress algae so you can run slightly lower chlorine. They're optional, but many owners love the soft water feel and steadier pH.

Boric acid vs. borax

Boric acid is pH-neutral and the simplest choice. Borax (sodium tetraborate) is cheaper but raises pH sharply, so it has to be paired with muriatic acid — more steps and easier to get wrong.

Frequently asked questions

What's the ideal borate level?: 30–50 ppm. Below 30 you get little benefit; above ~50 there's no added value.
Do borates replace chlorine?: No — borates suppress algae but don't sanitize. You still need chlorine, just possibly a touch less.

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Built & reviewed by a working pool-service pro. Target ranges follow CDC MAHC, PHTA, and Taylor guidance. Doses are starting estimates — add a little less than the max, re-test, and confirm against your product label. Educational tool, not a substitute for a water test or professional advice.