Koi ponds are fish ponds that contain only one type of fish: Koi. Koi ponds are considered desirable because of the many varieties and patterns of colors that Koi have.
Koi are a type of common carp that was originally used as a food fish in Eastern Asia. In 1820, Japan first began to breed Koi for color. The story goes that some rice farmers in Ojiya, a town in the Niigata prefecture, were keeping Koi as a food source for the winter months. The farmers began to notice some irregular pigmentation in some of their Koi. Instead of eating the odd colored fish, the farmers began to create koi ponds and breed their fish with their neighbors’. Eventually the Koi began to develop some of the patterns that we recognize in modern koi ponds. Specifically the Kohaku, a white koi with red marking said to resemble the petals of a cherry blossom, was popularized at this time. This breed of Koi was said to have originated from the Koi ponds of the Ojiya farmers.
It wasn’t until 1914 that the Niigata Koi were displayed at an exposition in Tokyo. Popularity for the fist skyrocketed across Japan and, eventually, the rest of the world. Now, Koi ponds can be found everywhere.
When building a koi pond, the main goal is the well-being of the fish. Koi prefer being kept between the 59 and 77 Fahrenheit range. In ponds with long winters where water temperature will drop bellow this range, ponds have a minimum depth of 1.5 meters.
The various color patterns of Koi stand out in a pond. These color patterns, which we find so attractive, are a severe disadvantage to koi. Predation is a concern when building a pond. The bright colors of a koi stand out to a predator like a neon sign. If you are in an area with predatory wildlife, such as herons or raccoons, the design of your koi pond should keep your fish safe. Trees can provide protection from aerial predators and any areas that look over the pond should be high enough that mammals can not reach in and grab a snack.
Color Variation and Breeding
Breeding koi is a difficult process. Because the desired color patterns are essentially a defect, the offspring begin to revert back to their original color. In the wild, decorative koi will revert back to their original black color within only a few generations. Breeders use a careful eye to select fry that have the correct color patterns and are not genetically deformed. The color patterns created when koi mate are limitless but there are some recognized standards. Much like show dogs, show koi can have strict guidelines governing their desired appearance. The size and placement of the colors is principle in judging Koi. If the color appears on the head versus the tail fin and other factors can increase or decrease a show Koi’s value.
Where ever they came from, Koi are certainly beautiful fish. This graceful fish will undoubtedly have a place in backyard ponds and koi ponds for centuries to come. With the limitless varieties of color and shape, you should always be on the look out for a unique and captivating Koi to call your own.