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Swimming Pools

What does a shock treatment do for a swimming pool?


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July 16, 2008 1:03AM

I assume you are using chlorine for your sanitizer: First, your swimming pool water must "BE IN BALANCE"! ALWAYS! You add chlorine to the pool on a regular basis either manually applying it or through an automatic chlorinator. The chlorine in the pool will begin to sanitize the water by attaching itself (we're talking molecules here) to the bacteria, algae spores, swimmer wastes, etc. Once it does, it still remains in the pool as chlorine according to your test kit, however it has become combined to the pollutant etc. and can do no more sanitizing. It still will show as a chlorine reading on your test kit but.....There are 2 kinds of chlorine you will have. One is combined chlorine (which cannot sanitize any longer( and (free chlorine. Free chlorine is the chlorine that hasn't killed anything yet and is still "free" and available to kill/sanitize. Now, when you have more combined chlorine in your pool than you have free chlorine, you have to separate the combined chlorine from the bacteria, etc that it is attached to. The only way you can do this is to ADD MORE CHLORINE. Or as some dealers say "SHOCK" your pool. A SHOCK DOSAGE IS 2 POUNDS per 10,000 GALLONS, for calcium hypochlorite (powdered shock) or 3 gallons per 10,000 gallons for sodium hypochlorite. THIS MUST BE DONE ON A BI-WEEKLY BASIS WHEN SWIMMERS HAVE BEEN IN THE POOL. IN ORDER FOR THE "SHOCK" TO BE EFFECTIVE YOU MUST HAVE THE pH AT 7.4 TO 7.6. If pH is too low, chlorine literally becomes so active it will do it's job and "gas of into the atmosphere" If pH is over 7.6 chlorine will not work. The key to a pool chemical maintenance is: BALANCE THE WATER. TOTAL ALKALINITY is the MOST IMPORTANT FACTOR. It controls pH.