Understanding Pool & Spa pH
pH describes how acidic or basic the water is. In pools and spas, pH interacts with sanitizer effectiveness, comfort and the tendency for water to become corrosive or scale-forming.
Test pH as part of your routine and make adjustments with products intended for your pool or spa system. Large corrections are usually better handled in measured steps rather than by guessing.
If pH keeps drifting, look at total alkalinity as well because the two are related. Use your equipment and sanitizer manufacturer's recommended ranges as the operating target.