maroon or maroon adn gold clown
maybe, a mid sized wrasse, anythign small will fore than likely be lion food, so you want probably 4 inch or better fish, if this is not a reef, a small butterfly(not juvenile, but small at maturity) or tang, koles are cool and 6 to 7 inch, but beware, the pics you find on the net, do them NO jsutice at all, they look 800% better in person
the tang is less aggressive, but is probably too big to be food, i have not had eels or lions, so maybe soeone else can say better about the tang
but it is asuggestion worth looking at, IMO