Need Fish ideas....

[Lpabsolute]

Hey guys, left my girl friend in charge of the tank while i went on vacation to vegas for a week. Came back and my Banggai Cardinal was no where in site. not sure what happend to him. i'm thinking of getting another fish to replace him. Not sure if i'm going to get the same thing or something different. The only thing in my tank now are two small clowns. Any ideas for a new addition to the tank? Some info on the tank below....

54g corner reef
250 MHL
75lbs live rock
Corals: mushrooms, zoas, cup coral, candy cane
Inverts: blue leg hermits, two emerald crabs, feather dusters, snails
Fish: two baby clowns