Okay. I see there's a little disagreement. First off, let's call it Red Slime Algae because that's what it is. Red Slime algae is actually Oscillatoria. Okay, yes it is a genus in the phylum of Cyanobacterium, but that's like only describing a leopard as a mammal. There are only 35 phyla in the entire animal kingdom. True Cyanobacteria or Blue-green Algae is green. Oscillatoria is not a diatom. It needs nutrients and photosynthesis to survive. I don't think silicates have any impact of Oscillatoria. 99% of the time you will see Red Slime Algae growing in low flow areas. That's also where detritus collects. Oscillatoria will help you to clean your tank. Syphon it out when it is in full bloom, about two-thirds through your light cycle. You'll notice it looks like there's isn't quite as much of it right before lights out, that's because it is reproducing at that time. And then in the morning before lights on there won't be very much of it, that's because it is photosynthetic. When you syphon it out you'll notice that it grows over a light gray dust - detritus. So, by syphoning it out you're removing it and the detritus.
