Alkalinity calculator

How much baking soda raises alkalinity — or acid to lower it.
Pool size
gal
Not sure? Work out the size
Alkalinity now
ppm
Total alkalinity holds pH steady, so it does not swing up and down.
Alkalinity you want
ppm
Good range: 60–100 ppm.
Using baking soda.
Type the size and your alkalinity reading.

How this is worked out

Baking soda (sodium bicarbonate) adds alkalinity almost without moving pH: about 1.4 lb raises 10,000 gallons by 10 ppm.
Lowering alkalinity is slower: add acid to bring pH down to about 7.0, then run jets or a fountain so the air brings pH back up. Each round lowers alkalinity a little.
The product label always wins — if it says something different, follow the label.

Questions

Is "Alkalinity Up" just baking soda?

Yes — check the label for sodium bicarbonate. Kitchen baking soda does the same job for less money.

What alkalinity should I aim for?

About 60–100 ppm for a chlorine pool, 60–80 for a salt pool and 50–80 for a hot tub.

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