Pool Alkalinity Calculator
Enter your pool volume and current and target total alkalinity. If you need to raise it, the calculator gives you baking soda. If you need to lower it, it gives you muriatic acid. The amounts come from the standard mass balance, cross-checked against established sources.
Baking soda to raise TA by 30 ppm
6.3 lb
100.9 oz
of sodium bicarbonate (baking soda)
Most pools aim for a total alkalinity of 80 to 120 ppm (some target 70 to 90 to make pH easier to hold). Alkalinity buffers pH, so get it into range first, then fine-tune pH. Dissolve baking soda in a bucket of pool water and pour it around the perimeter with the pump running, wait about 6 hours, then retest.
Alkalinity is the buffer, not the goal
Total alkalinity does not matter for its own sake; it matters because it stabilizes pH. Too low and pH bounces around; too high and pH drifts up and is hard to move. Set alkalinity into range first, then handle pH with the pH calculator. Start, as always, from an accurate pool volume, and see the full calculator list for chlorine, salt, and stabilizer.
Frequently asked questions
How much baking soda raises pool alkalinity?
About 1.4 pounds of baking soda per 10,000 gallons raises total alkalinity by roughly 10 ppm. Some charts round this to 1.5 pounds. This calculator scales the amount to your exact volume and target.
How do I lower total alkalinity?
With acid. About 25.6 fluid ounces of full-strength 31.45 percent muriatic acid per 10,000 gallons lowers total alkalinity by about 10 ppm. The acid also lowers pH, so plan to aerate the water afterward to bring pH back up while alkalinity stays down.
What should pool alkalinity be?
Most pools target 80 to 120 ppm. Some people aim a little lower, around 70 to 90 ppm, because it makes pH easier to keep stable. Total alkalinity is a buffer, so set it before you fine-tune pH.
Should I fix alkalinity or pH first?
Alkalinity first. It buffers pH, so a pool with alkalinity far out of range will fight you on pH. Get total alkalinity into range, let it circulate, then make small pH adjustments.
Can I use baking soda instead of pool alkalinity increaser?
Yes. Pool alkalinity increaser is sodium bicarbonate, the same thing as baking soda. Plain baking soda works identically and is usually cheaper, as long as it is pure sodium bicarbonate with nothing added.
Baking soda dosing from stoichiometry (1.40 lb per 10,000 gal per 10 ppm; popular charts round to 1.5). Acid dosing of 25.6 fl oz of 31.45% muriatic acid per 10,000 gal per 10 ppm, cross-checked against Swim University and TestYourOwnPool. Follow your product label, add acid in stages, and retest.