Aiptasia lol...
The LFS may tell you that stock lighting is OK for a bubbletip anemone but long term it really isn't, and when an anemone gets sick in a tank that size things can go south really quickly.
The above poster has a good suggestion with a torch coral, (or hammer or frogspawn) - they look a little like an anemone and have been known to host clownfish, just make sure your clown isn't too big for it, they can "love" them to death
