Rabbitfish (siganus) problem

[Green_fishy]

Hi,
I have problem with my Siganus guttatus. The fish has not eaten for a few days, it is lying on the bottom. Other fish (Acanthurus triostegus, ptarapogon, chrysiptera and rest) are fine, they swimm and eat. I saw siganus eating sand, I have 1-1,5 mm - maybe the grains are stuck somewhere? I don't now what to do :sad2:

 

[Jdub968]

I believe the rabbit fish will eat sand as a digestive aide. Other than being lethargic is he breathing heavy or does his belly look swollen