None unless you have a leak.
swimming pool
No.
To disinfect it.
Chlorine is used to disinfect Swimming Pools.
It is necessary because the chlorine kills all of the germs that enter the swimming pool.
Chlorine is not so much good for swimming but it is good for keeping the water free from harmful microorganisms, economically.
Chlorine is used in swimming pools for a few reasons. The most common are: 1. Chlorine acts as a mild disinfectant, it makes swimming in the water a more sanitary activity. 2. Chlorine also inhibits the growth of algae. Without chlorine, most pools would be green within a few days.
Swimming pools
chlorine
No. In fact chlorine is added to swimming pools to kill bacteria.
Probably the chlorine. I doubt if chlorine is healthy for frogs.
the higher the temp the quicker the chlorine loss