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Enter your latest test results. This works out what to add and puts the steps in the right order, because alkalinity changes pH and chlorine depends on stabilizer.

  1. Alkalinity first: add 6.3 lb of baking soda to reach 100 ppm.
  2. pH: add about 10 fl oz of muriatic acid.
  3. Stabilizer: add 2.5 lb to reach 40 ppm.
  4. Chlorine last: add 1.8 qt (58 fl oz) of 10% liquid chlorine to reach 4 ppm.

Run the pump between steps and retest before the next one. Never mix chemicals together.

Why the order matters

Alkalinity comes first because it buffers pH: fix pH first and it will drift straight back. Calcium and stabilizer change slowly and do not interfere. Chlorine goes last, since it works best once pH is in range and its dose depends on the stabilizer level.

Target ranges used here

Alkalinity 80 to 120 ppm, pH 7.2 to 7.6, calcium 200 ppm or more, stabilizer 30 to 80 ppm, and free chlorine at least 2 ppm or 7.5% of stabilizer, whichever is higher. See the full chart and where those numbers come from.

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