If you are keeping softies and a couple of fish, a Remora will work fine. If you want even better water quality for stony corals, a sump with a EuroReef ES5-2 would be better. For the ultimate in hang on skimming, a Deltec MCE600 would be the ticket, awesome skimming power, but it's not cheap because of the beating the US dollar is taking overseas at $446.00. Aqua Medic makes a good skimmer also, the Turboflotor. It's often overlooked, a bit bulky, but a good inexpensive skimmer, with a needlewheel design.