Blue Earth has a couple CBB, never had luck with one surviving long. The Filefish didn't work for me either. It ended up getting eaten by the powerhead. Had a Racoon and Pearlcale BFF that both did a number on the Aptasias. The Racoon didn't pick at coral, wouldn't eat frozen or prepared food. Once the Aptasia number was down it slowly starved to death. Then the Aptasia came back with a vengeance. The Pearlscale was taken back to the LFS. A Kliens BFF is supposed to be a good aptasia eater as well, haven't tried one yet. I am SPS dominant so picking to me is ok, I have tow toby puffers that sharpen their beaks regularly and do far more damage than a BFF. I wouldn't try a butterfly with a prized zoa collection although the racoon did not touch them