He is better off with no food than to be given food that is not good for him. Try lowering the water level so he does not have so far to get to the surface but he is going to have to get some meds I think for the swim bladder problem. The problem you are going to have is medicating in the very small container you have him in at this time. He also needs to be warmer at this time. To really give a fish with swimbladder problems a chance to see if the temperature will work it needs to be raised to around 82 degrees slowly and left there consistently for a period of several days to allow the gas build up in the swim bladder to be expelled.

I do not know at this time what else to tell you.

Rose