That unfortunately looks like velvet to me. I would pull the fish immediately and put it in qt. leave your display fishless for 72 days before adding any new fish. Here's some good info for you.
Defeating Marine Velvet Disease!
X2 don't treat in your main DT. you'll regret this later.It's usually better to treat the fish in a separate tank because the things that we use to treat it like copper will get sucked into the live rock and leach back into the tank.
Yes this post help me with my velvet problem.Arvind, sorry to see this. I'd suggest you check out Humblefish's post on R2R HERE. He has done a very nice write-up on treating Marine Velvet. Best of luck.
Planning to follow this method to the letter. All but three fish are in QT already. Hopefully tonight the remaining will also enter QT.Yes this post help me with my velvet problem.
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Good luck. I hope your pets make it.Planning to follow this method to the letter. All but three fish are in QT already. Hopefully tonight the remaining will also enter QT.
Thanks for all your responses.