You could however consider a euphyllia. They look anemone like and will be fine with the
PC lights that come with the tank. Plus clowns are about as likely to host a euphyllia as an anemone. I also agree that you are probably stocked out with your tank. Until a recent disaster I had only a pair of Ocellaris clowns, clean up crew and some low light corals in my NC24.
Now it is fishless as I decide which way to go. I believe that 2 or 3 small fish are the maximum you should have in a tank this small. I only have 4 (maroon clown, firefish, sixline and Atlantic pygmy angel) in my 54.