Sailfin tang Sails/fin rot?

[piranhaman00]

I have this tiny sailfin tang going through QT, he is entering the final round of general cure having been through 14 days of copper already. I have an image of when he is in the bag and some now, it appears his top Sail is starting to deform slightly, he has been with two large dart fish that could have easily dinged him up but wondering if this looks like fin rot to anyone? You can see in the pics the gouge out of the top sail.

Thanks for any help!

 

[Caruso86]

Looks fine to me! When I first got mine it had something similar but hes been just fine going on 3 months.