Mature Yellow Tang Stopped Eating

[Ken Roane]

Yellow Tang looks perfectly healthy but suddenly stopped eating four days ago. Any suggestions what I can do?

 

[Gumbies R Us]

Have you made any recent changes to your tank that could possibly causing this?

 

[Ken Roane]

Have you made any recent changes to your tank that could possibly causing this?

No Changes. Feeding has been normal and water quality good. 20 nitrate reading. Large Blue Tang, 2 butterflies, 1 raccoon, 1 file fish, 1 Niger trigger, juvenile Japanese dragon eel