[clown shrimp]

for a 55 gal tank you could get away with it if you have pairs, Like reefnoob1991 said, and also if you have multiple anemones. not cody anemones! most clowns prefer sebae anemones, carpet anemones, BTA's and Heractis magnifica anemones.

Ps what kind of clowns do you want to have?