It helps kill a lot of bad bugs in the water which in turn will help keep your chickens healthy, some people do the chlorine and some do the apple cider vin. I will look for the info that CL sent me and let you see why they do it. Its put out by a vet.Ive heard that to be true for flouride, but lots of home filtration systems (atleast CLAIM) to remove chlorine.
But anyway, the purpose is to keep the waterers clean then? Thats why you add the bleach?