Goldfish and Koi

Goldfish and koi are among the most popular ornamental fish, kept both in aquariums and garden ponds. They are available in many varieties with different colors, body shapes and sizes, with some selectively bred goldfish varieties suited to aquarium keeping, while koi are primarily intended for spacious ponds.

Goldfish (Carassius auratus) are hardy and long-lived fish, but require sufficient space and efficient filtration because they produce a significant amount of waste. Koi (Cyprinus carpio) can also reach a considerable size and require increasingly more water volume as they grow, making a garden pond the more suitable long-term environment for them.

When choosing these fish, consider their adult size, required swimming space, filtration needs and compatibility with other inhabitants. A properly planned environment allows goldfish and koi to grow well and develop their characteristic coloration and appearance.