Assuming it's a swim bladder issue, you could try:
ACETAZOLAMIDE (immersion) Dosage and Preparation Instructions for a 10g/38L Hospital Tank
Active Ingredient: Acetazolamide
Indication: gas bubble disease, edema, popeye
Brand Name: Diamox
Dose at 250mg per day for 3 days.
Replace the medication in ratio to the amount of water changed daily as needed to control ammonia.
Day 1 of Treatment
• Crush one 250mg tablet into a fine powder.
• Use a mini-blender or small hand-blender to thoroughly mix the powder with about 1 cup of marine
water.
• Allow the mixture to set for a few minutes.
• Gently pour off the dissolved portion of the mixture and discard any residue that has settled at the
bottom of the container. (Do NOT add the residue to the hospital tank).
• Pour the mixture into a high-flow area of the hospital tank.
Days 2 – 3 of Treatment
• Perform 50% water change.
• Repeat "Day 1" instructions.
You can use the above med concurrently with Furan 2 per package directions.
The Diamox may relieve any edema, which might help with the buoyancy issue, and the Furan 2 to combat any bacterial infection.
Also, if you can drop your temp to 74*F during treatment, it will help slow any bacterial infection.