Beautiful tusk. Thx for the feedback. I’ll get big snails and hope for best! No shrimp or crabs I’m afraid. I can get a 7 inch so s/b able to fight off aggression from tangs and angels. Will QT for 30 days. Thx again.Harlequin Tusk is a great fish to have in a large tank. They will hold their own but is not a bully. I have no opinion on the number of fishes in your tank, but if you think you have room, then a HT can easily be the center piece of your tank. Mine will eat small snails on the rock. He decimated the thriving population of Stomatella and the the various breeding small snails in my tank. As for small fish and shrimp, just wait untill he went to sleep before adding small fish. Dazed disoriented small fishes are irresistible to predators. He does not bother my clowns or other small wrasse. I am sure keep him well fed go a long way in keeping small fish safe.