Koi carp are, without question, the king of pond fish. With a maximum size of four feet in length, and prices reaching $16,000, quality koi are often regarded as more of an investment than a pet. There are many recognised colour and pattern varieties, all referred to by Japanese names relating to the fishes' appearance. A well-coloured, healthy koi is a beautiful fish, and provided some logical rules are followed, a pond full of these living works of art can be set up and maintained with the minimum amount of stress (both to you and the fish).
Many people are put off by the seemingly enormous amount of time, effort and money some experienced koi-keepers invest in their prized posessions, but in reality, as with so many aspects of the hobby, koi keeping can be as simple or as complicated as you want to make it