I hold a obnoxious green algae slime higher than my pool I tried the blue/grn algae cntrol and it did not work help out.
Answers: too much sun leading to low oxygen level, also you need oxygenating plants and by nouns of it a filtration system.
Is it an outdoor or indoor pool?
Do you use chlorine/bromine? (or is it one of those kiddy pools?)
It it's outside, try covering it
If it's not a kiddy pool check the chlorine/bromine levels, if they're to low that might be the problem.