In comparison to other skimmers, Seaclones are not widely respected. A search on any board will yield very few favorable comments. It's just a low end skimmer that's very hard to dial in. Not sure how much room you have between the tank and wall but if it's in the 4 inch range, a Remora would work great on a 55. You can mess with the Seaclone but doubtful you'll get great long term results, particularly when you compare it to other units.