Which algaecide did you use? The only one that we recommend is:Originally Posted by WorBryI do not believe algaecides actually precipitate out dead algae.Polyquat
The only algaecide we recommend using. Often sold in a 60% concentration as Algaecide 60 or something similar. Other kinds of algaecide have various problems, adding metals, foaming, bad smells, etc, depending on what they contain. Algaecide is most effective at preventing algae from getting started, and doesn't do very well against an active algae bloom.
Also, algaecides can help prevent getting an algae bloom, but they do not help (can actually hurt) the process of killing them.
@Smykowski...worbry's name has been added to the super secret list