Depends on budget, stock, available space. You can get some great canisters like fluval or eheim, but there not cheap, and if youe going to be stocking the tank heavily youd probably need two big canisters. Heck there are guys on here with 2or 3 fx5's on a 120! Peronally i like sumps. If you can get a good size sump tank you can set it up how you need it with whatever bio and mechanical filters you want. A 55g sump tank would be great, couple filter socks, filter sponges, bio balls or pond matrix and yoy got a great sump thatll handle almost any boi load you can fit in that tank.
Sent from my GT-S6810P using MonsterAquariaNetwork App