Courtesy Yoko Dam

Aquarium and ornamental fish can pose a major environmental risk. Introduced fish populations can establish as people release their fish into the wild, and the unregulated nature of the aquarium trade make this a difficult problem to overcome. Data is available on marine ornamentals, but data for freshwater species is lacking. More regulation is needed and trade policy needs to be developed and implemented to reduce risks to native species. A possibility is to only allow trade in revocable species, species that can be completely removed from the wild. Another possibility is the use of marketing to control for invasive species. The problem of aquarium fish has received inadequate attention, and needs to be studied more.

The introduction of foreign species into a population of native species without immunity to non-native diseases is a very serious issue. The import and export of ornamental fish to and from various countries can contribute to the spread of foreign diseases. Introduced pathogens are capable of causing damage to native fish populations and impacting the native ecology.