Tang with weird mark

[kfries]

I just noticed this weird blotch mark on the side of my tang. There is also a little white thing along his dorsal fin. He seems to be swimming around and eating well. I had not noticed this before. He has been in the tank for 5 or 6 weeks. The clowns and damsel were not very welcoming of him and had nipped one of his fins pretty good, but that all appears to be healed up and I have not noticed any aggression in the last 4-5 weeks. He does swim through the rocks quite a bit so I am not sure if it is from that or not. Has anyone else ever seen these kinds of marks on a tang?

 

[JumboShrimp]

<Bump>

 

[kfries]

The mark is still present. He knows has a smal cut in his tail. He is still very active and eating pellets, frozen and nori.

 

[FishyHotel]

I would say just keep an eye on it. I don’t have a lot of experience with fish diseases, but my sailfin tang gets marks with some regularity when she rubs against a rock so it’s probably nothing to get alarmed about. If there has been last aggression there is likely still some as things settle (hopefully) and it’s not uncommon for fish to dart at each other and brush the rocks during that.

 

[Jay Hemdal Verified Community Expert]

The mark is still present. He knows has a smal cut in his tail. He is still very active and eating pellets, frozen and nori.

It could be a disease known as tang thumbprint or fingerprint disease. Not much is know about it:

https://www.reef2reef.com/threads/tang-fingerprint-disease.335665/