I have a 6' X 24" X 18" tall shallow reef. Right now I have a pair of return pumps, and two WP25's in the tank. I have a mixed reef with some softies (zoas mostly), and some SPS. The WP25's are pretty powerful and mounted at opposite ends of the tank. I can easily get a wave that nearly splashes out of the tank on W1 setting at full speed. I go back and forth between that setting and the "else" setting. Else moves more water, but I almost never see my fish because the current is so strong. Is the wave action enough for SPS? I can visibly see my birds nest coral moving with that setting, and it seems more friendly to my fish. I can post a video later, but just generally looking for some opinions. Here is the tank from my build thread: http://www.marinecolorado.org/forums/showthread.php?26797-Starting-my-rimless-shallow-reef