Free tool
Total Alkalinity Calculator
Baking soda to raise total alkalinity, muriatic acid (aerate method) to lower it — dosed to your exact pool volume.
How to use this calculator
- 1Enter your pool volume
Don't know it? Use the Pool Volume Calculator first — this tool is built to work with that gallon figure.
- 2Choose raise or lower TA
Enter your current and target total alkalinity readings from a test kit or strip.
- 3Pick your product
Raising uses baking soda (sodium bicarbonate). Lowering uses muriatic acid via the aerate method — enter your product's exact concentration.
- 4Read your dose (and the procedure)
Raising TA is a straight dose. Lowering TA also shows the aerate-method procedure, since technique matters as much as the amount here.
Frequently asked
Questions about total alkalinity
Why does lowering TA require a special procedure, not just a dose?
Muriatic acid reacts with the water it touches almost immediately. If you pour it across the whole pool surface, it mostly just lowers pH everywhere without giving the alkalinity time to off-gas as carbon dioxide. The standard technique is to turn off circulation, pour the acid slowly into one deep spot away from skimmers and returns, let it sit undisturbed for a few hours, then re-aerate (fountains, waterfalls, or agitating the surface) to bring pH back up without re-raising alkalinity.
Will raising total alkalinity also raise my pH?
Yes, slightly. Baking soda (sodium bicarbonate) nudges pH upward a small amount as it raises TA. If your pH is already on the high side, retest after adding baking soda before deciding whether you also need acid.
What's the ideal total alkalinity range?
Most pool professionals target 80-120 ppm, with 60-120 ppm considered acceptable. Alkalinity acts as a buffer for pH, so keeping it in range makes every other chemical adjustment more predictable.
What if I don't know my pool's exact volume?
Use the Pool Volume Calculator first to get a solid estimate, then come back here — the two tools are designed to work together.