Something Keeps Attacking My Blue Tang

[rattslik]

I keep walking up in the morning to find my blue tang has been attacked by something. It has been happening every night for the last week. There is a big crab in the tank which is two times the size of the tang but it the crab got hold of him he would be dead. I have got 2 ocolaris clownsfish 1 scopas tang and 1 bicolor blenny. I dont know what is causing this help would be appreciated.

 

[Albertan22]

The scopas would be my prime suspect, but honestly I doubt the fish would be fighting at night after lights out. Is he jamming himself into some crevice when he sleeps and scratching himself up? Did you quarantine him? Are you sure he’s not scratching himself because of an inch infection? Those blue tangs are notorious for being magnets for disease and parasites.

 

[rattslik]

At night he always seems to sleep on my leather coral which doesnt like it that much and i didnt quarantine the fish due to not having a quarantine tank

 

[Albertan22]

Keep a close eye on home for awhile and see if he’s scratching against rocks or the sand bed. Those vermatid snails in the foreground of your picture (my tank has them too) could cause scratches like that if the fish is scratching against them. While you are watching him closely, pay attention to any aggression from the other tang or any other fish. One of the other fish could be chasing it causing it to dart into the rock work and scratch itself on the vermatids even.

 

[rattslik]

Are vermatid snails dangerous?

 

[Albertan22]

Are vermatid snails dangerous?

No they’re just a pest. If they get really bad they can annoy corals and cause them to close up. In my experience they eventually die back when a tank matures.