Whats the cheapest and easiest way you guys have come up with to get a decent looking black background. i was thinking maybe even a black garbage bag and tape it to the back of the tank, I don't have a show tank but I dont want it looking too tacky either. Maybe like a black tarp or something. What have you guys done? and I dont want it bad enough to paint the back of my tank, because I know thats what some people here do.