I had an especially evil melanurus wrasse in my old 75g reef who killed off the following inverts...
- Scarlet skunk cleaner shrimp (bashed it to death, but never ate the body)
- Peppermint shrimp
- Cerith Snails
- Turban snails
- Mexican Turbo Snails
- Nassarius Snails
- The occasional blue leg hermit crab (he may have wiped them out, I don't remember for sure)
... He also killed my leopard wrasse, pencil wrasse and possum wrasse, so they DO have the potential to be aggressive and predatory. That being said, I know plenty of people who have kept them for years without complaint. So good luck :bigeyes: