Coral Beauty

Question
I have a 55 gallon reef aquarium.  My coral beauty has begun to have dark places around its eyes and mouth.  It is still eating well, but I am concerned.  I did a water change four days ago and noticed the the changes on the fish last night. The coral beauty seems to be the only fish affected. Any suggestions would be great.  Thanks!

Answer
Mikayla,     I wouldn't worry too much unless the change continues. I think it probably got startled and hit the rock and is bruised. It is rare but may have been stung if you have an anemone. It can cause discoloration but,it is rare. Though your tank space is limited for a reef system. I would not add anything to the water. A good sign would be that it is eating. Make sure she has no paralyzation in that area. If not,like I said, I wouldn't worry. If the problem continues or he has any behavior change let me know. Good Luck, Tina