Change Your Font Size:

Water Chemistry Calculator

Size Of Pool

20,000 Gallons

Before adding salt, test your pool water for the current level of salt.

Current salt reading

2,800 ppm

pH is the measure of how acid/alkaline the pool water is. If pH is too low, the water can be corrosive to pool equipment. If pH is too high, then the chlorine becomes much less effective for sanitization.

Current pH reading

7.2 pH

Total Alkalinity (TA) is a measure of the total alkaline substances found in the pool water. The results of improper TA levels range from corrosion of metal pool parts, staining of the pool, burning eyes, cloudy water and reduced chlorine efficiency.

Current alkalinity reading

90 ppm

Cyanuric Acid (Stabilizer) is very important to the performance of your chlorine generation system. It's a mild acid that helps prevent the breakdown of chlorine due to the sun's ultraviolet rays.

Current cyanuric reading

40 ppm

Total Hardness is the measurement of the total amount of minerals that are found in your pool's water. Too much calcium hardness will cause scaling in your pool and too little will cause the pool water to become corrosive.

Current hardness reading

300 ppm

Phosphates are common components of most pool water sources and they can be introduced by external factors (e.g. fertilizers). For the majority of pool owners, phosphates are not an issue for either health or pool water management. However, in some instances, because phosphates is a food source for algae, you may find it a challenge to keep a chlorine residual in the pool. If you are having trouble with keeping chlorine residual, consult your local pool professional.

Show Results

About Your Pool Water Chemistry

  • Decades of pool and spa water management has led to a standard series of water chemistry recommendations for your swimming pool. These recommendations are generally aligned with those of the Center for Disease Control (CDC) and The Association of Pool & Spa Professionals (APSP) and the National Swimming Pool Foundation (NSPF). Hayward recommends you follow the attached guidelines as well as the advice of your local pool professional to enhance the quality of your pool water and your swimming enjoyment.
  • Important Tip: It is best to adjust your water chemistry in a particular order—Salt, cyanuric acid, hardness, total alkalinity and pH. This can help minimize the amount of chemicals you need to bring your pool water to the proper levels.
  • Recommended Water Chemistry Levels
    • Free Chlorine: 2-4 ppm (Ideal)
    • Combined chlorine: 0ppm (Ideal)
    • pH: 7.2-7.8
    • Cyanuric Acid: 30-50 ppm (Note: Indoor pools should have 0 ppm)
    • Total Alkalinity: 80-120 ppm
    • Total Hardness: 200-400 ppm
    • Salt (for any Hayward salt chlorination system): 2700-3400 ppm
    • Metals: 0 (Ideal)
    • Phosphates: less than 50 ppb (Ideal)