convict dying

[ram897]

https://goo.gl/photos/JoLhNRm55eCpxqAL8
Hope that image works.
I have a 5year old female convict who has a 55 gallon tank all to herself. She stopped eating over a week ago and has slowly been getting fat and losing color. She has now been nose down for 3 days. I have tried a few suggestions from my local fishstores such as peas-won't touch, aquarium salt-nothing yet, and water changes. One seems to thing she swallowed a rock and the other thinks dropsy. She has gotten to the point that she cannot float normally. She tried to get off her nose and had to work really hard and ended up in the same position. I have resigned myself to the fact that I will probably lose her but wondering if anyone has any other suggestions. I don't really want to pump my tank full of meds because I will use the tank again. Sucks because this was my first fish ever and had since she was 3 months old.