Another paint idea - some ppl have used the spray-on speckled texture paint which is coloured like sand, that way when u r looking at the tank the bottom appears to be sandy even tho its bare bottom. I think there are some threads here showing how this turns out. Def go with a lighter colour to brighten up the discus. I painted mine white, and I don't mind it, but if I could redo it i would try the textured light coloured sand look.