I have a red leopard sailfin Blenny. He’s about 4 inches long and I’ve had him for around a month. Two nights ago, I noticed that a section of scales on his right dorsum side was missing. When I woke up today, the injury looks deeper, wider, and is now over the top and onto the left side. Other tank occupants are three clowns and a damsel (little bittie guy who has never been aggressive) and some medium sized hermit crabs. What could be causing this? Could the hermit have done it?