Usually a chlorine based chemical is used. But chlorine doesn't kill it all. See link for more.
Sanitizer.
There are many options of sanitizers for pools ex: chlorine, bromine, copper, etc...
Sodium hypochlorite can be used.
Chlorine
Chlorine
chlorine or the filter
chlorine
clorine/borine
Chlorine is the most used (to disinfect and keep clean), but Bromine is also used.
Chlorine.
to keep the water clean and kill germs
Chlorine is generally added to swimming pools and other water attractions in order to keep the water clean. Doses of chlorine typically come in small tablets.
Chloride is put in pools to keep you away from bacteria,example:athlete's foot.It also protects your skin and eyes.Chloride can damage your hair,so the best thing to do is to wash it after swimming. I hope I've helped.
*clean chlorine.
HOCL or hypochlorus acid
Silver. oxygen.
Probably not maggots but mosquito larva. Need to keep your chlorine in check.