I picked up a 48x48x17 tank a couple of weeks ago... been driving me nuts trying to visualize a finished system. Because of my Man-cave layout, one side will be against a wall... no center of the room tank. With that part established, I drilled it for back corner overflows. I did add an extra hole for WC drain line. My initial thought is a huge Zoa Garden with a large school of Anthias. What would you do? No Volcanos! Seriously.