It really does depend on the lionfish. I have two in with a complete clean-up crew (including a cleaner, a coral banded and peppermint shrimp. Emerald, red mithrax, porcelain, hermit crabs. ) and neither of them have even looked at them. Not that I'm suggesting you load up on shrimp or anything, but it does really depend. My shrimp are also huge, so maybe that is the difference.