Planted Tank Guru
Join Date: Jun 2004
Location: Baton Rouge, LA
stevekx500: The algae itself won't fizz directly, as you might have seen with an H2O2 spot treatment.
Instead, you'll get an overall fizz. Could be mild. Or could be intense, if you normally have pearling plants and the water is already thoroughly saturated with oxygen. It resembles the "false pearling" many see after a water change.
If successful, the BBA will typically start to discolor within a day or two, and start decomposing around day three.