Troubleshooting a Goldfish Floating Upside Down: Swim Bladder, Tumors, or Constipation?

Possible Causes

• Swim Bladder Disorder: Common in fancy goldfish. Caused by gulping air, constipation, infection, or anatomy.
• Internal Tumor/Cyst: Displaces swim bladder.
• Bacterial/Viral Infection: Systemic illness affecting buoyancy.
• Severe Constipation: Impaction presses on swim bladder.

Try These First

1. Fast for 2-3 days.
2. Feed cooked, skinned peas (laxative).
3. Pre-soak pellets so they sink; avoid floating food.
4. Check water quality (ammonia, nitrite, nitrate, pH).
5. Add Epsom salt (1 tbsp/10 gal) in a bath for constipation.

When to Euthanize

If no improvement in a few days, the fish is suffering. Humane euthanasia (clove oil overdose) is kinder than prolonged distress. See this resource for more details.