Hippo Tang losing color?

[rcbc3384]

Hello
What would make my Blue Hippo Tang lose the color (blue) around its eyes? Its skin also looks motled almost like the scars from a teenage acne in humans

 

[Steven Pro]

It might be Marine Head & Lateral Line Erosion,
http://www.reefkeeping.com/issues/2005-06/sp/index.php