@Foskett96 -- I'm not sure why people are saying clowns are aggressive. They will defend themselves, but they do not harass. I have two clowns and a firefish goby in a 40g. They have been fine together. I also had a sixline wrasse that was fine with the clowns and firefish.
I will say that dottybacks can be aggressive, and so can angels. And some angels nip corals.
If you get any tangs, then yes you will need a bigger tank. Otherwise, the clowns, firefish, wrasse, etc are all good in a 30+ gal