help to indentify a disease

[ele]

My Pictus had a growth on his head. I treated him for 2 weeks using Prazipro. Now all the area behind his head has ...something, like hairs...they are grey and about 2 mm long, but it acts normally. Can it be fungus? I have read that the weak and stressed fish might get it.
What do you think can be done? ...and can salt help instead of medications?

[Roan Art]

Best to post a very clear picture so we can get a better idea of what you are referring to.

Roan

[ele]

oh...I can see it only when the fish is moving and this things is beating...but I will try