Shock

Okay, Im really new to the whole pool chemistry and maintence thing, but after being on this site frequent for the past couple months. I have a quick question before I take off and hope someone may have a simple responce when I get home. What exactly is done by shocking your pool, and what is needed to do it. also when and how often does it need to be done. are there tests you can take to determine if your pool does need to be shocked. Thanks.

Shocking is the process of raising your free clorine high enough to burn off organics, ammonia, and chloriamines in the water. It is sometimes called 'breakpoint chlorination'. How high you need to shock depends on how high your CYA is (and in extreme cases, how high your combined chlorine is, but this problem very RARELY comes up so just don't worry about it)....see the Best Guess sticky at the top of the chlorine forum. If you have combined chlorine of .5 ppm or greater you need to shock.

Non chlorine shock does not work the same way. It will not destroy choramines. In fact, it will show up as combined chlorine on testing. I personally do not recommend it's use in an outdoor chlorine pool.

IMHO, the best thing to shock with is bleach. Remember, shock is a verb (something you do to your pool), not a noun (a specific product).