I"m a newbie to salt water so this isn't really a suggestion as much as just telling you what I have in my 55. Others with more experience than I may disagree with the amount or type of fish I have in mine, but I have a 55 with a valentini puffer, spotted hawkfish, banded clown and a coral beauty. But I will say to be careful and make sure that if you get a more temper mental fish that you don't include the more peaceful living mates as it will stress them out.