just a caveat
Algaecides
Common ingredients to almost all commercial algaecides are either copper
or simazine both are toxic to fish and higher plant life.The dosage needed to kill
algae without harming fish or higher plants is hard if not impossible to determine.
Dying algae may releas toxins into the water or its decomposition may deplete oxygen from the water and cause an amonia spike.
Water clearing agents
Flocculents should not be used in tanks with fish.Flocculents are positively
charged compounds that bind negatively charged particules so they bind together
and fall out of solution resulting in clearing.Since algae cells are negatively
charged Flocculents will clear green water.
Theres a possible problem tho,the gill surfaces of fish also carry a negative
charge.The Flocculentscan bind the gill filaments together destroying the gill
structure.-Anne
Keep in mind algaecides only mask the problem, not solve it. Chances are it could come back if the situation in your tank, as in whatever is favorable for the algae to grow, stay the same.
Algone is not an algaecide. I've used it very successfully. BUT, in my reef tank. It's essentially a Nitrate and Phosphate sponge. I can see where it could be used in FW (I wouldn't choose to do so however), but regular replacement would be needed and get costly IMO.