Mandarin Discoloration

[ReeferPrime]

My mandarin is doing fine ,but recently I have been seeing patch of spot on him and is looks white.He not thin or starving I don't know what to do.
please help me.

 

[melypr1985]

Can you post a picture please? Have there been any changes in your tank recently?

 

[Humblefish]

Did you see this at night or first thing in the morning when the lights come on? Mandarins secrete their mucous coat at night, so they will look white.