I need a hang-on as I do not have a sump, I am also limited on the space behind the tank to 4 1/2″. One final thought, I believed the Seaclone to be the best candidate for the ozonizer, as it snaps together with no gaskets (so no premature wear on the gaskets from the ozone), however the guy at Aquarium Systems said the ozone would prematurely wear the impeller on the powerhead, but I have read through your FAQ’s and it seems a lot of ozonizer are run this way. I truly appreciate your thoughts on this, I would like to do it right the first time, and avoid a