Listless Pond Fish: Fluke Infestation Emergency

Symptoms

1500-gal pond, 9 fish (3–8″), 72°F. Fish listless, isolating, one dead. Brown water fixed with carbon.

Diagnosis: Gill/Skin Flukes

Microscopic parasites (Dactylogyrus, Gyrodactylus) attack gills/skin → lethargy, isolation, death. Very common in spring.

Immediate Treatment

1. If ONLY koi: SuperVerm (formalin + malachite green) – kills goldfish, orfe, tench.
2. Mixed species: Potassium permanganate (PP) or Fluke-Solve (praziquantel). PP: 2 ppm, bypass biofilter, aerate heavily. Fluke-Solve: safer, follow label.
3. Salt (if no plants): 0.3% (3 lbs/100 gal) = 45 lbs for 1500 gal. Helps osmoregulation, kills some parasites.

Urgency

Flukes kill fast. Treat immediately. Get medication from pond store or online today.