Despite all my water chemistry being spot on besides fc which I always keep a little high I am always getting algae on bottom of pool liner. This algae never has spread and made water green but nonetheless it’s always growing on bottom of poop in spots water is always clear. I’ve brushed and slammed but it always returns. Should I add algeacide? I know it’s not needed but in my case I can’t seem to cure the problem. Is algacide dangerous? Cancer causing? Please help . I don’t understand why this is happening. My filtration, vaccume, and chemistry is all good all the time . Why ??????