well if ur gonna go w/ sharks get atleast a 180, tho preferably a 240-300, get some shark compatible fish (basically no angels, wrasses, triggers, puffers, or really mean eels) wait for the tank to get established (10mos-a year) have a really good skimmer (rated for like 3 times the tank size) a nice refug w/ lots of lr, clear swimming space for him as well as some caves