Testing Swimming Pool Water

Info provided by Latham Pools

Fiberglass Pools Use & Care Manual

Proper testing procedures insure accurate chemical readings.

1) Read and carefully follow testing instructions enclosed with your test kit.

2) Rinse test kit tubes with pool water before filling the tubes for testing.

3) Take water sample for testing 12 to 13 inches deep in pool. Do not take water sample from the surface water in the pool; this will effect the accuracy of the test.

4) Always read the test results against a white background.

5) Always test chlorine first, then test the pH.

6) Keep your test kit in a cool, dry place.

7) Replace test agents each year. The reagents lose their accuracy due to exposure to heat and sunlight.

When to Test

1) Chlorine residual – Every day, if no marked change every other day or twice per week.

2) pH level – Every day, if no marked change every other day or twice per week.

3) Total alkalinity – Every four to six weeks.

4) Calcium hardness – Every two to three months.

5) Metal content – Every two to three months.

6) Cyanuric acid, total dissolved solids – Every six months. The pool water should be tested for chlorine residual, pH level, total alkalinity, calcium hardness, copper and iron after each rain of consequence or upon addition of more than eight inches of fresh water.