What are you gonna be keeping in the tank. You say you don't want to keep sps in the tank now, but you never know about the future. You can't go wrong by upgrading your pump. More flow is always better. My only recommendation is instead of buying something that would be good for now, buy something that could accommodate any change of feelings you may come across. Its cheaper to buy one really good pump than to buy one now and upgrade it again later. Just my two cense. Hope it helps. Also make sure you can get the water out of the fast enough to accommodate what ever pump you get. Good luck.