Goldfish are among the most commonly kept and most poorly kept pets, with welfare standards that rarely reflect their actual needs.
Goldfish in bowls suffer from ammonia toxicity as their own waste accumulates in unfiltered water. Oxygen depletion in small bowls causes physiological distress. The myth that goldfish have three-second memories has contributed to a cultural acceptance of inadequate care. Goldfish kept in appropriate pond or tank conditions with filtration, adequate space, and companions live long, healthy lives with demonstrably complex behaviour.