I have a 36 gallon bowed display tank and a 33 gallon tank and they each have a fluval aquaclear 50 HOB filter and (forgot what kind) about a 6inch(ish) sponge filter in the corner as well. Should I consider investing in a canister filter or possibly and undergravel filter? The 33 will become a shrimp taqnk when fully cycled and the 36 I will be breeding peacock gudgeons or killifish. Anyone with experience have any suggestions, as well as any other ideas anyone may have. I am open for all suggestions so I can provide the best tank possible for my babies!