Ummm this is a very addictive hobby. Just as druggies go from one drug to a different drug, reef keepers go from one tank to another tank...usually larger. Eventually, your future 55 gallon won't even be large enough!!! Oh and I'd suggest a 75 over a 55. That extra 6" front-back is a HUGE improvement. 55s suck for aqua-scaping, with only 12" of depth!!