What chemical levels do I need to test for regularly?

The four main tests to perform with a test kit are pH, chlorine (or other sanitizer residual), Total Alkalinity and Calcium Hardness. Cyanuric Acid levels, mineral content, Total Dissolved Solids and Acid or Base Demand tests may also be performed as needed.

How often do I need to test the water?

I should say everyday, but I realize that's a bit much for most people. Commercial pools are required to check chlorine levels every hour and record their findings in a log, however the "backyard lifeguards" should check their pH and chlorine levels at least 2-3 times a week. Chlorine should be fed continuously through a feeder device to maintain a consistent level. Total Alkalinity and Calcium Hardness levels tend to fluctuate less, so weekly testing should be O.K.

What are the recommended levels?
• pH: 7.2 - 7.8
• Chlorine: 1.0 - 2.0 ppm
• Total Alkalinity: 80 - 120 ppm
• Calcium Hardness: 180 - 220 ppm, though some say 200 - 400.
• Cyanuric Acid: 25 - 50 ppm
• Total Dissolved Solids: 500 - 5000 ppm

How long do my reagents last?

Typically one season. Reagents lose their strength over time and can also be ruined by direct sunlight and temperature extremes. Replace your reagents annually.

Can I use reagents from other test kits with my test kit?

No; drop size, concentration and color variation will provide inaccurate results.

Can I use a chlorine test kit for bromine?

If you have a DPD test kit, you need simply multiply the test result by 2.25 to obtain the bromine equivalency. This works because bromine is over twice as dense as chlorine.

My test kit shows no Chlorine, even though I know it's there...

If chlorine levels are excessively high, the content can bleach out DPD, a reagent commonly used for chlorine testing. Either dilute the sample with chlorine free water, or double the # of drops of DPD, and multiply or divide accordingly.

There has been evidence that excessively high levels of stabilizer, or cyanuric acid, can cause a phenomenon called chlorine lock. Levels above 100ppm of cyanuric acid (CYA) may prevent chlorine from registering and possibly sanitizing. Lower CYA levels by dilution.

share this page