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Pool water testing – introduction


After reading this article, you should be able to:

– Compare different pool water testing methods for chlorine.

– Explain the procedures for collecting water samples used in testing.

– Explain the method for color-metrically testing the pH of water.

– Explain what elements constitute water hardness.

– Explain characteristics of low and high water hardness levels.

– Interpret the results of various testing procedures



Regular and exact testing of swimming pools and spa pools is essential to maintain a healthy, clean pool environment. Proper control of all the variables involved in pool chemistry is assured only by constantly monitoring the water, evaluating the findings, adding chemicals, and maintaining automatic chemical feeders as necessary to control proper water balance. While water testing is now easier due to the development of commercial test kits, the quality of the test kits varies considerably. A number of companies produce laboratory-quality kits for more exact chemical readings, but the general-use kits are inexpensive and can be used for spot tests by trained pool personnel. Laboratory-quality kits should be cared for, secured, and used only by a trained operator.



There are several brands of water testing kits available


Electronic controllers that read, evaluate, and mechanically adjust the pool water chemistry have simplified the testing and maintenance procedures associated with water chemistry balancing. The applicator need only conduct periodic checks (confidence checks) and simple maintenance procedures to insure that the electronic readout agrees with the water tests. The mechanical controller does everything else, including turning on pumps and adding the proper chemicals to balance the water chemistry.



Automated controllers can sense and automatically treat for both chlorine residual and pH balance.


Regardless of the system used, all applicators must follow basic rules when testing water. Disinterest, sloppy instrument handling, hurried procedures, bad reagents, poor choice of sampling location, or inaccurate measurements will lead to problems.