Is this ich, and what should I do?

[saltyfishy123]

Some of my fish have been having some white substance on there skins, first my labouts fairy wrasse, but now its all cleared up then my sailfin tang, all cleared up... And my yellow tang isnt wanting to go with the flow and clear.


Someone suggested that it may be lymphocystis, but please Im not sure if I should QT since it may stress all the fish out.

Heres a pic of the tang.