I've got a 35 gallons tank, with a common plecostomus gibbiceps (6'' long), two severums (4.5'' and 6.5''), a blood parrot (6'') a small Loch clown (1'') and a couple of very small algua eaters (1'' each). I know, that's a lot. That's why I recently bought a new 130 gallons aquarium (yay!)...