Is he eating, and if he is, what is he eating? Color loss, especially around the face is usually a result of some kind of stress. If your water quality is good, then you should see the red color come back soon, so long as the angel is eating properly. Angels have a need for lots of different things in their diet, especially sponges and algaes. If you aren't already, start using Angel Formula frozen fish cubes from Ocean Nutrition. A friend of mine with a queen angel was having the same problem, except most of the color was fading and turning to white. After two weeks on Angel Formula, the queen got her color back, and now looks amazing!