You can also use Seachem's Excel for algae control (2x-3x recommended dosage) works great. Gluteraldehyde, which may be one of the ingredients in Excel also works. You might these useful:
http://www.aquaticpl...rid-all-my.html
http://www.aquaticpl...tead-excel.html
http://www.aquaticpl...ment-algae.html
Gluteraldehyde action against algae is most likely due to its antimicrobial properties. In stronger concentrations, it is used for disinfection. This is essentially the same principle as hydrogen peroxide. I suspect the peroxide would cost less. The claim is that Excel (as an isomer of gluteraldehyde) provides a biologically available form of carbon. Always suspicious, I'm not sure if it would affect growth more than say, adding dead leaves to the substrate. I don't have any data there.