hey now I have a question concerning algea. I have an aquaticlife T5ho 30" on my 20 gal L I have a clear glass canopy and the fixture is 3" above the clean cover. I use 2 mil of excel daily. and the regular seachem schedule of iron, potassium and the regular flourish. The light is on 8 hours a day. I've got 1 oto in the tank. You'd think I'd have algea but I don't. How come? It couldn't be that measley little bit of excel daily or could it?