I have 4 black backgrounds and 1 light blue one, the light blue one takes less powerful lights to brighten the tank, but the black one looks better with proper lighting. The blue tank is one I bought that someone had previously painted and it looks like they used a brush to paint it on, silly I know, so i havent tried to scrape it all off. Black gets my vote, but you cant go wrong with either. Just stay away from light blue and those horrid flowered/planted ones. If you do decide to paint it use latex spraypaint.