Hello, I just got this new blue hippo tang 3 days ago and tonight I noticed these white spots on him. What are they are they just stress spots or ick? And what should I do? Pls help the water parameters are perfect btw. I just separated him from a clown tang that would attack him
He is probably stressed and that lowered his resistance. You should set up a qt tank for him and treat him for what ever his illness is. Once we get better pics. Your other fish may or may not have to be treated. Once you solve all of this though, you will have to use an acclimation tank to introduce your tang into your hopefully bigger than 70 gallon tank. Or the tang police are going to be knocking on your door.
Getting closer/better photos will help, but I think I can see spots on the tail fin. That is a good indication that the problem is marine ich, not stress spots (those don't show up on fins). However, depending on how severely the clown tang attacked it, they could be fin damage from that.