Best of luck with your fish!

I would feed some medigold while you're at it, if you can get some. I am in Connecticut and have some on the off chance you are from here.
Also, it could be something that has already damaged your poor fishy internally, so remember you are doing the best you can, even he if doesn't make it!

Can you force feed him at all? I have heard of people doing that with a syringe.
Laura