I'm too lazy to clean the back panel. So in my last tank and my current 750g we used black pond foam and mounted flat slab rock to the back wall. And then started seeding it. We got some of the brightest and most metallic branching gsp - so as it grows instead of being a mat it creates towers going up as well and adds a bunch of dimension to the GSP. Our back wall also has acros, torches, frogspawns, duncan and mushrooms. Our tank is 48" from front to back. Having the color and the life on the back wall of the tank draws your eyes through the tank and really gives a chance for the depth to be perceived. If you goto the webcams you can zoom in thru the center of the tank and see the assorted corals on the back wall - o2manyfish.com