Commonly called Koi in the western world, and originating from the common carp, Cyprinus carpio,  the name “Koi” comes from Japanese and simply means “carp”. In reality the name Koi thus includes both the dull grey food fish as well as the brightly colored ornamental varieties.

The correct name for the beautiful ornamental carp is Nishikigoi – a name that literally and very descriptively means “brocaded carp”. If you wish to become an afficionado of this fish, it would be wise to learn and use the correct term, as Nishikigoi were developed in Japan and the language of the koi world, or more correctly the Nishikigoi world, is and will remain Japanese. Japanese is used not only to name the varieties, but also for many of the terms used to describe the colours and traits of these beautiful fish.

As an aside, in Japanese koi is a homophone for another word that means “affection” or “love”; koi are, therefore, symbols of love and friendship in Japan. The koi is also an often recurring symbol in Irezumi, the Japanese art of traditional tattooing.

Nishikigoi (or Koi) varieties are distinguished by coloration, patterning, and scalation. Some of the major colors are white, black, red, yellow, blue, and cream. The most popular category of koi is the Gosanke, which is made up of the Kohaku, Taisho Sanshoku, and Showa Sanshoku varieties.

The earliest types of Koi produced were bred from the fish kept as food by rice farmers, to supplement their winter diet. From time to time coloured mutations would appear amongst these carp and some were kept as pets. It seems most likely that the first types to appear were the red and white varieties now referred to as Kohaku. From these early beginnings breeders were able to breed other colour varieties. The next types to appear were Sanke and Showa, both with three colour patterns of red, white and black, but with different proportions of the three colours.

In 1904,during the Japanese-Russo war, the Munich Research institute for Fisheries in Germany gave 40 western carp to the breeders in Japan. Sadly only 1 Mirror Carp and 6 Leather Carp survived the trip. Nevertheless, these German Carp were immediately introduced into the Japanese breeding programs and cross-bred with their indigenous carp. These seven Doitsu carp turned out to be the genetic backbone of Doitsu carp and later the Doitsu koi as we know them today.

Initially the Doitsu carp were only used to enhance the production of edible fish and not to create ornamental koi. The newly introduced German carp did not have scales and was easy to clean and prepared for food.  But unlike what many people believe,  the main reason for the introduction of the German carp into the food market was the bulkier body shape and thus more meat to eat. The hybrid vigor caused by the cross breeding of Doitsu and Japanese carp was a major contributing factor in producing more fish meat. In addition, the Doitsu carp grew remarkably well and outperformed the local carp.

It was only at a later stage that the German carp was actively used to enhance the ornamental koi carp – and what a large contribution they made to the selective breeding of Nishikigoi. In 1906,  a new strain called Doitsu-Asagi came into being.  Kagami Uroko, or mirror scales is a characteristic feature of German carp. Kagami Uroko not only dominated the scales of Nishikigoi, the German carp were also much easier to take care of than their Japanese counterparts. It is thus that ease of care became a trait carried forward to today’s modern ornamental carp.

The most obvious difference was the scalation on the newly produced koi. Less obvious but as important were the body shape changes that took place. The long and much thinner body conformation of the Japanese koi changed to the beautiful bodies of modern koi. Almost all koi varieties today do have Doitsugoi blood in their genetic makeup. In fact, the superb body shapes off modern show winners would not be possible without the genetics inherited from the Doitsu carp.

Japanese recognize thirteen basic classes of Nishikigoi, or Koi and these classes are now accepted throughout the world. Within each of these classes there are a number of sub categories. We cover these in the images below.


Koi are not suited to aquariums, except when they are very small. Even then it is recommended that they be kept in a proper Koi pond. You can read about the requirements for a Koi pond here


Nishikigoi , or Koi do not breed true! So, having a pair of expensive show champions means that out of 20,000 eggs only 10 will grow in to that coveted perfect fish.  But that does not stop the breeders trying to perfect the species. New koi varieties are still being actively developed. Ghost koi developed in the 1980s are a hybrid of wild carp and Ogon koi, have become very popular, and are distinguished by their metallic scales. Butterfly koi, also known as long-fin koi, or dragon carp, were also developed in the 1980s, and are notable for their long and flowing fins. They are hybrids of koi with Asian carp. However, there are those who do not consider Butterfly and Ghost koi to be true Nishikigoi.

With so many Koi being bred today, quite often a totally new combination is found – and those combinations may not fit in any of the thirteen categories. As they become more popular, some of these unique Koi will eventually become consistent enough for their features to form a new category. So, keep your eye on the breeders.

The beauty of Nishikigoi truly deserves the accolade “Living Jewels”. We hope that you discover much more by studying the images and information below, and we wish you joy with your Nishikigoi!

Finally, we have this advice for novice koi hobbyists: Do not get daunted by the flurry of Japanese terms corresponding to the various breeds of this fish. Get accustomed to the terms slowly, and enjoy the learning process. The best starting point of this learning process is more often than not with the three most established and most popular breeds of koi, namely the ‘Kohaku’, the ‘Sanke’, and the ‘Showa’. ‘Gosanke’ is the term used to refer to these three breeds taken together. Talk often to other Koi enthusiasts – and if you can, ask breeders to point you in the right direction. They recognise the potential of baby Koi very early on! The more you hear these terms, and the more you watch what other hobbyists do, the sooner those bewildering koi terms will become part of your everyday vocabulary!

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