Goldfish Lying on Side: Swim Bladder, Injury, or Infection?

Symptoms

Calico goldfish on bottom, on side, moves briefly when netted. Other 4 fish fine. Water tests OK. Treated for ich (unlikely). Fish 2.5 years old.

Possible Causes

• Swim bladder disorder: Common in fancy goldfish. Caused by constipation, infection, anatomy.
• Internal bacterial infection: Kidney, liver, or systemic.
• Injury: From spawning, decor, or tankmate.
• Parasites: Flukes, though usually affect all fish.

Action Plan

1. Leave in pond if not bullied (stress of moving may kill).
2. Add aquarium salt (1 tbsp/5 gal) + MelaFix to pond – safe for all.
3. Feed cooked peas (fiber) if eating.
4. If worsens: Hospital tank with antibiotics (Maracyn I & II), salt, pristine water.

Contagion

If infectious, others already exposed. Isolation not necessary unless bullying occurs.