calcs.homes
calcs.homes
Enter your current and target pH and we'll tell you whether to add soda ash or muriatic acid, and how much.
Estimate only — pH response isn't perfectly linear. Add gradually and retest.
To raise pH, we multiply the pH increase needed by pool volume (per 10,000 gallons) and by 30 oz of soda ash (sodium carbonate) per full point. To lower pH, we use the same formula with 80 fl oz of muriatic acid (31.45%) per full point instead. A small adjustment of a tenth of a point or so only needs a few ounces either way.
Soda ash and muriatic acid sit on opposite sides of the pH scale — one alkaline, one a strong acid — so only one is ever dosed at a time, based on which direction you need to move. The 7.4-7.6 target range matters because it's close to the pH of human eyes and skin and the range where chlorine sanitizes most effectively; outside it, chlorine loses potency and swimmers may feel irritation.
7.4 to 7.6 is the target range for most pools — close to the pH of human eyes and skin, and the range where chlorine sanitizes most effectively.
Chlorine products, rain, bather load, and aeration from water features all push pH up or down over time — regular testing (2-3 times a week) catches drift before it becomes a bigger problem.