one can will work fine if you don't mind hiding a couple of sponge filters in there run em on air or a powerhead,and make sure you have plenty of flow (extra powerhead or 2 ) seems like everybody's answers revolve around spending big$$$.....but 1 big can is a lot to start with if you were to use 2 aqua clear 50 powerheads for circulation , you could attach a sponge filter to each and have plenty of filtration,and you can get the sponge filters for about $10 each
