Pool Alkalinity Calculator

Aim to keep most pools between 80 and 120 ppm. If your test result lands inside those numbers, there is nothing to add.

pH does best at 7.4 to 7.6, though anything from 7.2 to 7.8 works. Check pH separately from alkalinity.

A reading below 80 ppm calls for baking soda. Above 120 ppm, you will want muriatic acid, the strong acid sold for pool use. Both doses below assume 10,000 gallons, and you can adjust them to fit your own pool.

To bring alkalinity up, use baking soda. In a 10,000 gallon pool, 1 lb 6 oz lifts it 10 ppm. Got 20,000 gallons? Use twice as much. For 5,000 gallons, cut it in half.

For larger lifts, repeat the dose and retest.

Not sure how many gallons you have? Work out your pool volume before dosing. A 16 x 32 ft pool averaging 4.5 ft deep holds roughly 17,200 gallons.

Enter your pool's gallons once and the site will remember them and fill them in on every dose calculator, so you don't have to scale these numbers by hand.

To bring alkalinity down 10 ppm, add 26 fl oz of muriatic acid (the common 31.45% strength) per 10,000 gallons. Use twice as much for 20,000 gallons, or half for 5,000.

When you dose chemicals:

1. 1. Run the pump so everything gets mixed well.
2. 2. Dose a single chemical at a time, near a return jet.
3. 3. Always pour acid into water, not the other way around.
4. 4. Store and use acid away from chlorine, because the two together are a dangerous mix.
5. 5. Give it 30 minutes, then test pH, since acid pulls pH down too.

It's better to add acid a bit at a time and retest than to pour in the full dose. Retest alkalinity before deciding whether to add more acid, and check pH 30 minutes after each addition.