Yellow tang split doral fin

[105man]

My yellow tang has two very clean vertical splits or slices in its dorsal fin, not quite all the way to its body. No other problem signs, and it has always done well. I have had it about 6 months.

Any ideas?

Thanks.

 

[Guy W]

my clown had some long slices on his tail fin. he actually gets them often, and they heal up in a few weeks and it looks normal. I think my Flame Angelfish fights with him.