Thanks for the info, I acually found his thread and gonna try it out; but like you said, since he is not eating Im not sure what to do.
You can use the straight 3% solution as described above, or presoak some food & use a syringe & tubing to get either mix down to his gut. Below is a good article that explains & shows pics on how to force feed a fish.
http://www.mchportal.com/fishkeepin...eding-mainmenu-81/540-force-feeding-fish.html
Repeat for 5 days or until the fish is back to eating the pellets on his own.
This procedure has already saved a few fish on MFK that were in the exact same boat as yours. (not eating, sunken belly, etc)
Good luck!