To disinfect it.
swimming pool
Chlorine is added to swimming pool water to disinfect it.
It is necessary because the chlorine kills all of the germs that enter the swimming pool.
If your talking about Swimming pool its because your pool has chlorine in it and chlorine kills fish :(
chlorine
The swimming pool at the Landmark Hotel in London is 15-metres. It's a heated and chlorine-free swimming pool. One can enjoy swimming in this pool without worrying about the side effects of chlorine, especially if one is pregnant.
The liquid chlorine formula used for swimming pool maintenance is typically sodium hypochlorite (NaClO).
the higher the temp the quicker the chlorine loss
Probably the chlorine. I doubt if chlorine is healthy for frogs.
If the combined chlorine in a swimming pool is a negative number, it indicates a testing error or miscalculation. It's important to retest the water using a reliable pool water testing kit to get an accurate reading. Negative combined chlorine levels are not physically possible in a swimming pool.
You can swim in a pool without chlorine or salt they just keep the pool clean. but if you do it can give you bad skin
Any one or thing swimming in the pool will reduce the amount of free chlorine available in the swimming pool. Dog hair body fats and other impurity's will take up free chlorine in the pool thereby reducing the amount of effective chlorine available. Dogs bring into the pool more contaminants than do humans for AA lot of various reasons.