Public aquariums house millions of fish in conditions that vary enormously in quality, with animal welfare science increasingly providing evidence-based standards for tank size, social housing, environmental complexity, and humane practices.
Fish welfare in aquariums presents the same challenges as other captive settings - meeting species-specific behavioral needs in artificial environments. For many open-ocean species, no aquarium tank is large enough to allow normal ranging behavior. Territorial species in community tanks experience chronic stress from inability to establish proper territories. The welfare impacts of transport, handling, and acclimatization are significant. Public aquariums that prioritize visitor spectacle over animal welfare may house species that cannot be kept welfare-positively. The best aquariums have moved toward housing species for which captive welfare can be genuinely good, while phasing out species whose needs cannot be met.