How to Adjust Total Alkalinity & Calcium Hardness

Alkalinity

• 1

  Turn on your pool filter. Test your pool water, using a testing kit or test strips. Alkalinity should be 80 to 120 parts per million (ppm). Alkalinity increaser will be needed for reading below 80 ppm, and alkalinity decreaser will be needed for levels above 120 ppm.

• 2

  Add 1lb. of alkalinity increaser for every 10,000 gallons of pool water. This will raise the alkalinity by 10 ppm. Adjust as necessary, depending on the alkalinity reading and pool size. Use alkalinity decreaser at the same rate to lower alkalinity.

• 3

  Run the filter for eight hours. Re-test using the water testing kit or strips. Adjust again as necessary.

Calcium Hardness

• 4

  Turn on the filter. Test the water, using a kit or calcium hardness test strips. Many test strips don't have calcium hardness readings and must be purchased separately.

• 5

  Adjust calcium hardness levels based on the readings. Normal levels are180 to 220 ppm as indicated by the testing kit. Add calcium hardness increaser (calcium chloride) at a rate of 1 lb. per 10,000 gallons of pool water to raise calcium levels 5 ppm.

• 6

  Add 1 lb. of calcium hardness increaser through the pool skimmer for every 10,000 gallons of water. This will raise the calcium hardness by 5 ppm. High calcium hardness readings can be decreased by partially draining your pool or using a calcium hardness decreaser product. The dosages for these vary widely, based on specific product.