Enter current and target chlorine and pH levels to get exact dosing amounts for any pool size.
Free chlorine should be maintained between 1–3 ppm (mg/L) for residential pools and 1–5 ppm for commercial pools. Below 1 ppm, algae and bacterial growth can occur. Above 5 ppm, the water may irritate eyes and skin.
Pool pH should be maintained between 7.2 and 7.6. At the ideal 7.4, chlorine is most effective. Above 7.8, chlorine efficiency drops significantly and scale forms. Below 7.0, water becomes corrosive to equipment and surfaces.
For 65% granular chlorine, you need approximately 1.54 g to raise chlorine by 1 ppm in 1 kL. For 50 kL from 0.5 ppm to 2 ppm (raising by 1.5 ppm): 1.54 × 1.5 × 50 = 115 g. This calculator works it out automatically.