Fish kept in home aquaria are among the most numerous companion animals globally, yet their welfare is poorly regulated and often inadequately understood by owners.
Aquarium fish are frequently housed in conditions that cause chronic stress and shortened lifespan. Bowls and small tanks prevent normal swimming behaviour, destabilise water chemistry, and deny territorial species adequate space. Social species kept alone suffer isolation, while territorial species kept in overcrowded tanks experience chronic stress from competition. Wild-caught marine fish experience traumatic capture — often using cyanide stunning in some regions — and high mortality during transport. Aquacultured marine fish are preferable from a welfare and conservation perspective. Education at point of sale about species-specific needs is critical but often absent. Improving aquaria welfare requires better retail standards and owner education.