Well the ich is starting to fall off which means the treatment is working. I lowered the salinity slower than normal and I'm making sure he is offered a variety of food. He's feeding quite well now which is a good sign.
My friend is very happy with this as this is the only large fish she has left after the outbreak.
One tip for everyone treating marine ich is make sure you have sufficient lighting. If you have dull or insufficient lighting you are less likely to see how bad the fish is affected.
Current tank 260g FOWLR.
Fish: Moorish Idol, Powder Blue Tang, Hippo Tang, J Emperor Angel, 3 Chromis, 2 Black & White Clowns, Yellow Tang,