Here are the parameters for properly balanced swimming pool water.
- Free Available Chlorine: 1-5 (ppm)
- Combined Available Chlorine: <.2
- pH range: 7.2-2.8
- Total Alkalinity: 80-120 (ppm)
- Calcium Hardness: 200-400 (ppm)
- Cyanuric Acid: 30-50 (ppm) *100 is maximum
- Copper: < 0.2
- Iron: <0.2
- Phosphates: <=100 (ppb)
- Total Dissolved Solids: <3000 ppm
- Salt Level: approx 3200 (ppm) *varies per manufacturer
Water that is unbalanced may be corrosive, or scale forming. For example, a pool with a pH below 7.0 or a calcium hardness level below 150ppm can corrode a gas heater's heat exchanger within months which can be costly. A high pH, total alkalinity, or calcium hardness level can cause scale build-up which can clog heat exchangers, chlorinators, or small pipes.