Planted Tank Guru
Join Date: Jan 2010
Location: Contra Costa CA
I have used a canister like that on several tanks of about that size (45 gallons, some 3' long, some 4' long). Sure helps to use a spray bar. Makes a great river tank.
I am running the AC 110 HOB on 2 tanks. 72 gallon bowfront and 45 gallon. It is a lot of flow for the 45 gallon, but that is a bit of a river set up, so it works OK. On the 72 gallon it is not a lot of flow, and is actually one of 2 filters.
I would work with the canister on the smaller tank. More options fro altering the inlet and outlet to moderate the flow to suit the fish. The HOB filters pretty much have one outlet, the weir, and that is it.