If you are looking for something small, a RG is a nice fish to have, brillant colours and they stay small. A group of blue-eyes anthias makes a fascinating sight and they are pretty easy anthias to keep. A pair of percs perhaps? Or a single lionfish, heard they are pretty disease resistant. Well, there are lots to choose from. Go visit some sites, do abit of research....liveaquaria is a nice site to check out the fishes, they even list their difficulty. Not a bad place to start.