Snails Dying in 160-Gal Prefab Pond

160-gal prefab, river plants, snails, mussels, clams, algae eater, 6–8" goldfish. Snails dying, empty shells. Asks if algae eater eats them.

Top Snail Killers

1. Salt: Even trace salt kills snails. Goldfish tolerate it; snails don't.
2. Ammonia/pH swings.
3. Starvation: Most common. Algae eater + goldfish outcompete.
4. Parasites: Wild-collected snails carry trematodes.
5. Predation: Goldfish eat small snails.

Diagnosis

• Test pH, ammonia, salinity.
• If params OK & plenty of algae/detritus → likely parasites or predation.
• Wild snails = parasite vectors. Nearly impossible to eradicate.

Management

Monthly 20% water changes, stable KH, no salt. Accept some loss. Don't collect from wild.