I have a similar situation going on. This is involved, so bear with me. Two weeks ago the male of my breeding angels that I have had for about 6 years was floating upside down, and could not swim. I put him in a smaller tank, and put some pimafix in the water. His stomach was swollen, and had red spots on his fins and tail. I put him in an
epson salt bath twice a day for 10 minutes. I did this for a week. The swelling and red
spots were gone. Now instead of floating upside down, he is laying on the bottom. He
is breathing well, and is alert and responds to me when I do up to the tank. But after
two weeks, he still was not eating and was getting weak. I decided to try putting infusoria in the tank like I do for baby fish, as he would not eat anything at all. After several day of infusoria 3 times a day he is stronger. Yesterday he ate one flake. This
morning he ate 2. This afternoon he ate 3, and this evening he ate one more. He is
still getting infusoria. He is more active and is trying very hard to get up and swim, and
is getting close to it. I do not know if he will actually make a complete recovery, but
he has come a long way. I thought I was going to loose him several times. It is a slow
process, but what is there to loose? His mate misses him, and did not eat for 2 days,
so I put another angel in to keep her company. She is doing well. Good luck with yours! Angels are special.