Last year towards end of August our above ground pool 48"x18′ round pool developed these black spots all on the bottom,sidewalls and ladder.I do not have any idea where these black spots came from,but we could not get them out and ended up throwing the pool away.What could have cause these black spots and why towards end of season when we had no problems all summer?
The black spots can be what is commonly referred to as black algae. There is no particular season when this occurs and there are chemical treatments developed to help clear up this problem.
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