Speaking of white lines, I have a 3 inch yellow tang that has developed white lines on eack side of its body that run from the top of his head, jus behind the gills, to his front fins. It started at the top of his head and I thought that he may have been trying to go through too small of openings in the rocks because it looked a little raw. He eats fine and does not appear to be affected. I am trying to get a good picture. Any ideas???