Agreed, Steve, but I remind myself that there are hundreds of types of red, green and brown algaes. It looked like it affected the tips of the green, but that was about it. I'm going to change my RODI filters, do a water change and keep up with the H2O2. I turned the lights on the FOWLR back on yesterday afternoon. 90% of the algae on the rocks is dead fuzz now. I'll go in there with a brush and get a little off at a time. The glass is still spotless.