i would recommend that you do a fish only tank. from what ive heard corals are far less forgiving than fish. if i were you i would avoid damsels. though they are easy to keep, they surely wont be the only kind you want to keep. and they will be aggressive. i would recommend a clown fish, royal gramma a hardy goby, hardy blennie. something like that, easy to keep, fun to watch and not aggressive. just so you know when that person said a 55 gallon was inexpensive he was saying that in comparison to larger tanks. believe me a 55 gallon will still be expensive. welcome to the hobby, and get as much advise and do as much reading before you spend and $ or make any decisions about what your going to buy. trust me, if i could have done it differently i believe i wouldve.