Our vet came over and did the procedure, it was very short, only a couple of minutes. Though uncommon, tumours do happen in fish, if they’re not affecting them then it’s best not to operate, as operations come with risks, but in this case it was decided it was for the best. Our Moorish Idol had to undergo an operation a few months ago as he had a tumour growing on his lip affecting his feeding. The Moorish Idol has a tubular snout, filled with long bristle like teeth, they poke their snouts into crevices to pick out small crustaceans for food, they also eat corals, sponges and tunicates whilst living amongst flat reefs in the Indo-Pacific Ocean. When fighting is observed the fish are promptly separated. We have had scarred fish in the past, this is typically from fighting that occurs amongst the same species. The noise and movement would be enough to irk them and put them off exploring it. Fish are pretty smart when it comes to avoiding danger though, if there was an exposed pump they would avoid it. If we have pumps in the tanks to create more water flow, all the pumps will have guards around the propellers. We keep all of our filtration away from the tanks the fish are in. Fish do scar if they are damaged like that, though dentist tools are not usually found near fish tanks! The main causes of fish scarring are either through fighting or equipment like pumps or filtration systems in tanks. He has some pretty bad scarring, which he got from landing on dentist tools when he tried to escape one time. In the film 'Finding Nemo', the character 'Gill' is a Moorish Idol. If they have a short dorsal fin, which does happen as it lures some species of fish to nip at it, the fish will be seen as weaker than those with super long trailing fins, who were able to avoid being nibbled.

It’s believed this extended fin is to show off to potential partners about how attractive they are. They elegantly glide through the water with their elongated dorsal fin trailing behind them.

The Moorish Idol (Zanclus cornutus) is a very handsome fish in my opinion. Image courtesy of Brocken Inaglory on Wikimedia.

Finding nemo fish