I painted the back of my new/used tank black. The Orange and Yellows just pop out at you, but the purples of the Acei and the Demasoni you just cannot see unless right up against the tank. Part of that is because the lights on this used one sucks, but another is the dark background. I had a black background on the old tank and had the same issue.

Anyone know what would be a good color to use for a background that would still make the light colors explode, but also let the darker fish show up too??

Iv seen a real trend at aquariums around here with the blue backgrounds...sort of a medium blue...not too dark...not too light.