How to raise alkalinity in a pool The short answer To raise alkalinity in a pool, add baking soda (sodium bicarbonate, sold as “Alkalinity Up” or “Alkalinity Increaser”). About 1.4 lb raises 10,000 gallons by 10 ppm. Aim for 60–100 ppm, or 60–80 in a salt pool. Spread it over the water with the pump running, and test again after a few hours — the calculator below gives your exact amount.
How much baking soda your pool needs Alkalinity now
Total alkalinity holds pH steady, so it does not swing up and down.
Alkalinity you want
Good range: 60–100 ppm.
Using baking soda.
Type the size and your alkalinity reading.
Step by step Work out the dose with the calculator on this page.
Spread the baking soda over the surface with the pump running. It dissolves easily; brush any that settles. A big dose goes in parts.
Wait about six hours, test again, and add the next part only if alkalinity is still low.
Then check pH: raising alkalinity lifts it a little.
The product label always wins — if it says something different, follow the label.
Why it happens Alkalinity is used up slowly by acid: rain, trichlor tablets and the acid you add to lower pH all bring it down.
Soft fill water can start it low after draining and refilling.
Questions Is alkalinity increaser the same as baking soda? Yes — both are sodium bicarbonate. Plain baking soda from a store is the same chemical, and usually cheaper.
Will raising alkalinity raise pH? A little. If pH is already high, raise alkalinity slowly, and lower pH afterwards if it needs it.
What should alkalinity be? Between 60 and 100 ppm for most pools, and 60–80 ppm for a salt pool, where pH tends to rise.
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