The canister filter would work if it was set up properly. IME, most canisters should be below the tank they're filtering to get proper function out of them. For instance, I tried putting mine up on a table to get it off the floor (my cabinet sucks and needs an upgrade, no room for filters or anything), and started getting endless air bubble burps and a drop in performance. Setting it back on the floor cured that. There are likely exceptions and YMMV of course.