Too much chlorine in the pool?

Too much chlorine at certain times my be better than not enough, but there is a point where too much chlorine is dangerous in your aquatics facility.  Chlorine is a sanitizer as it leaves a residual in the pool water.  As chlorine continues to rise in a swimming pool, chlorine takes on the role of an oxidizer.  This means too much chlorine in the pool can start to chemically change other chemicals in the pool into hazardous byproducts.  This is of course the process of too much chlorine making a chemical reaction within the base of pool water. The CDC recommends 1ppm of Chlorine sanitizer in your swimming pool for safety and disinfection.

Testing for too much chlorine in the pool due to false positives

One problem with the oxidizer effect is that having too much chlorine in your pool will also cause false readings within your pool test kit reagents.  Test kits are designed for a specific range of chlorine. Normally, this is around 1-10PPM or parts per million of chlorine.  When you have too much chlorine in the pool though, this chlorine causes false-readings.  In certain test kits, chlorine will oxidize out the test powder and give you a brief flash of color.  This indicates the presence of chlorine, but it is also not quantifiable because it oxidized the testing reagent.

too much chlorine in the pool

Testing for high quantity or too much chlorine in the pool

You can test for high levels of chlorine by using dillution.  Take your water sample and mix it 50 / 50 with deionized water.  This will help to lower the quantity of chlorine in your test and then you multiply your result by 2.   This is a way to prevent oxidizing of the reagents and allowing you to achieve a satisfactory result.  You might even need to go as high as 4:1 where you add 75% distilled water and 25% pool sample.   After that point, if you have too much chlorine in the pool, you can consider sanitizer paper.  This is what the local health department uses to test for very high levels. Lastly, if you see your pool has turned yellow, this is a strong indication that there is far too much chlorine in the pool.  You will need to start dilluting it immediately, and close your facility to patrons while you handle this emergency situation.

Get help for too much chlorine in the pool

If you struggle to maintain chemical balance within your aquatics facility, Contact Pool Envy and we can help get you on a successful path to water management.

Wisconsin, Green Bay, Appleton, Oshkosh, Illinois, 

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Swimming pool contractor licensed in Wisconsin and Texas. CPO Certified and PHTA Certified instructor.