What kind of power filter are you running right now?What I did was,over the weekend,went to pet supply plus to buy another dual power filter for my 55 gallon.I bought a Marineland pengiun 350.It cost me 35 dollars on sale.The original powerfilter that I have hooked up right now came with the 55 gal.tank kit.Which works ok,but the marineland pengiun 350 is awesome.Also you can use a canister,but in my opinion,a canister is worth having when you decide to upgrade to a 90 gallon or above fish tank.