DOITSU KOI

Doitsu-goi 
Originated by cross breeding numerous different established varieties with "scale-less" German carp (generally, fish with only a single line of scales along each side of the dorsal fin). . There are four main types of "Doitsu" scale patterns. The most common type (referred to above) have a row of scales beginning at the front of the dorsal fin and ending at the end of the dorsal fin (along both sides of the fin). The second type has a row of scales beginning where the head meets the shoulder and running the entire length of the fish (along both sides). The third type is the same as the second, with the addition of a line of (often quite large) scales running along the lateral line (along the side) of the fish, also referred to as "Mirror koi". The fourth (and rarest) type are referred to as "Armor koi" and are completely (or nearly) covered with very large scales that resemble plates of armor.

KOROMO KOI


  • Koromo 
  • A white fish with Kohaku style pattern with blue or black edged scales only over the hi pattern. This variety first arose in the 1950s as a cross between a Kohaku and an Asagi. The most commonly encountered Koromo is an Ai Goromo, which is coloured like a Kohaku, except that each of the scales within the red patches has a blue- or black-edge to it. Less common is the Budo-Goromo which has a darker (burgundy) hi overlay that gives it the appearance of bunches of grapes. Very rarely seen is the Tsumi-Goromo which is similar to Budo-Goromo, but the hi pattern is such a dark burgundy that it appears nearly black.

OCHIBA KOI


Ochiba
A light blue/gray koi with copper, bronze, or yellow (Kohaku style) pattern, reminiscent of autumn leaves on water. The Japanese name means "fallen leaves."

KUMONRYU KOI

Kumonryū 
Kumonryu is a black doitsu scaled fish with curling white markings. The patterns are thought to be reminiscent of Japanese ink paintings of dragons. They famously change colour with the seasons. Kumonryu compete in the Kawarimono category.

OGON KOI



Ōgon (黄金?) A metallic koi of one color only. (hikarimono 光者). The most commonly encountered colors are gold, platinum, and orange. Cream specimens exist but are very rare. Ogon compete in the Kawarimono category and the Japanese name means "Gold." The variety was created by Sawata Aoki in 1946 from wild carp he caught in 1921. Recently the metallic skinned Ogon is being crossed with ginrin scaled fish to create the ginrin Ogon with metallic skin and sparkling (metal flake) scales.

KAWARIMONO KOI

Kawarimono (変わり者?) A "catch-all" term for koi that cannot be put into one of the other categories. This is a competition category and many new varieties of koi compete against each other within this one category. Also known as kawarigoi

KINGGINRIN KOI


Kinginrin (金銀鱗?) A koi with metallic (glittering metal-flake appearing) scales. The name translates into English as "gold and silver scales." Often abbreviated to Ginrin. There are Ginrin versions of almost all other varieties of koi, and they are fashionable. Gin-rin refers to sparlking, glittering scales as opposed to the smooth, even metallic skin and scales seen in the Ogon varieties. Recently these characteristics have been combined to create the new "ginrin Ogon" varieties.

SHUSUI


Shūsui (秋水?) The Japanese name means "Autumn Water." The Shusui was created in 1910 by Yoshigoro Akiyama, by crossing Japanese Asagi with German mirror carp. The fish has no scales, except for a single line of large mirror scales dorsally, extending from head to tail. The most common type of Shusui have a pale, sky-blue/gray color above the lateral line and red or orange (and very, very rarely bright yellow) below the lateral line and on the cheeks

GOSHIKI

Goshiki (五色?) A dark koi with red (Kohaku style) hi pattern. Appears similar to an Asagi with little or no Hi below the lateral line and a Kohaku Hi pattern over reticulated (fishnet pattern) scales. The base color can range from nearly black to very pale sky blue.

BEKKO

Bekko (鼈甲?)
A white-, red-, or yellow-skinned koi with black markings sumi (?). The Japanese name means "tortoise shell," and is also written as べっ甲. The white- red- and yellow varieties are called Shiro Bekko (?) Aka Bekko (?) and Ki Bekko (?) respectively. May be confused with the Utsuri.
Utsurimono (写り者?) 


A black koi with a white, red, or yellow markings. The oldest attested form is the yellow form, called "Black and white markings" (黒黄斑 Kuro Ki Han?) in the 19th century, but renamed Ki Utsuri (黄写り?) by Elizaburo Hoshino, an early 20th century koi breeder. The red and white versions are called Hi Utsuri (赤写り?) and Shiro Utsuri (白写り?) respectively. The word utsuri means to print (the black markings are reminiscent of ink stains). Genetically the same as Showa but lacking either red pigment (Shiro Utsuri) or white pigment (Hi Utsuri/Ki Utsuri)

ASAGI


ASAGI
Asagi (浅葱?) A koi that is light blue above and usually red, but also occasionally pale yellow, or cream generally below the lateral line and on the cheeks. The Japanese name means "pale greenish blue." Sometime incorrectly written as 浅黄 (light yellow).

Tancho

Koi with a red head patch are called "Tancho." Most common are "Tancho Kohaku (all-white Koi with Tancho)," "Tancho Sanshoku (white Koi with Sumi similar to Shiro Bekko, and with Tancho)," and "Tancho Showa (Showa Sanshoku without red markings except for Tancho)," etc. However, "Tancho Goshiki (Koi of five colors with Tancho)," and "Tancho Hariwake" are rare.
Tancho do not form a single, independent kind of Nishikigoi; they all can be bred from Kohaku, Taisho Sankshoku or Showa Sanshoku. Their red patch happen to show up only in the head region. Tancho, therefore, can not be produced in bulk even if you so wish.
The essential point for appreciation is the red patch in the head region, of course. The red head patch sitting right at the center of the head region is the best. The white skin is also important as it is the milky white color that sets the red head patch off to advantage. The Sumi of Tancho Sanshoku and Tancho Showa are the same as Bekko and Shiro Utsuri respectively.

Shōwa Sanshoku (or Showa Sanke)

Shōwa Sanshoku (or Showa Sanke)
A black koi with red (hi ) and white (shiroji ) markings. The first Showa Sanke was exhibited in 1927, during the reign of the Showa Emperor. In America, the name is often abbreviated to just Showa. The amount of shiroji on Showa Sanke has increased in modern times (Kindai Showa ), to the point that it can be difficult to distinguish from Taisho Sanke. The kanji, , may be read as either sanshoku or as sanke.

Sanke Pattern

Pattern
The red and black markings on the white body must be artistically balanced.  This means that a certain color must not be confined to one side or one end of the koi only. 
The red-over-white pattern may be continuous or 'stepped', but the over-all effect of white and red balancing each other should be the ultimate consideration.  Many people prefer stepped koi and understandably so, since this pattern ensures red and white alternating with each other. Sanke with a 'hi' pattern that runs continuously from head to tail is known as 'aka sanke'.  Aka sanke is less desired, since the predominantly red body makes it look heavy. 
A white area separating the tail and the red marking nearest the tail is known as a tail stop, and is considered desirable. A red mark on the lips of a koi (also known as 'kuchibeni') is a 'plus' if it enhances the over-all package of the koi.
A good sanke has a red pattern (but absolutely no black color) on the head. The head pattern must extend slightly beyond the eyes but should not reach the nose or lips, leaving a white area in the front end of the head.  A fully red head (referred to as 'menkaburi') that makes the koi look 'hooded' is considered negative.  Nonetheless, some koi look good despite having it, so don't let it prevent you from buying a koi that you like.
A round patch of red on the head is considered nice.  If this red patch is the only red marking on the sanke, then the koi is called a 'tancho sanke', a highly-prized koi variety among the Japanese since it looks like their national bird.  If there are other red markings on the body of the koi, then the round head patch makes it a 'maruten' sanke.
The sumi of a sanke must be distributed in the koi body such that they collectively add balance to the koi.  Their presence should enhance the 'kohaku pattern' and not degrade it.  Old-style sanke koi are heavily endowed with sumi.  Modern sanke exhibit a sparser distribution of sumi, but these should be clearly defined and solid black nonetheless.  Koi experts also prefer sumi spots that are positioned over the white body. Conversely, sumi spots over hi markings are less desirable to them.

General Description of Sanke


'Taisho Sanshoku', or 'sanke' is the term applied to a koi that has a white body with red and black markings. The black markings are in the form of spots that are generally confined to the body above the lateral line. Sanke as a koi breed was established around 1917.
Appreciation Criteria
The criteria for appreciating or judging a Sanke is the same as those of a Kohaku, with the addition of criteria for its black markings.   In fact, it is said that a good Sanke is actually a good Kohaku that has been further enhanced by black spots that add elegance to the totality of the koi.
Color
The shiro (white) base color of the body must be unblemished, thick, snowy, and even milky. The shiro must not exhibit any yellowish tint.
The hi (red) markings on the white body must be solid, deep, and evenly-colored throughout the entire body. The edges of these markings (also known as the 'kiwa') must be very defined, or as they say, 'sharp as a razor.'
The hi color may vary from koi to koi, but it should be of uniform hue within an individual koi.  Different koi exhibit different hues, from a deep persimmon orange to dark, purplish red.  This entire range is acceptable, although judges invariably have their own preferences.   
The sumi (black) markings of a Sanke must be deep, solid, and shiny lacquer-black. The shape of every sumi spot must be clearly defined, with its kiwa or edges as sharp as possible.  Undeveloped sumi (also known as 'sashi') may appear mottled dark blue or gray instead of solid black.  This is not bad for a young koi, since sumi actually develops as the koi grows older.  In fact, spotting a potential champion at a young age involves good anticipation of how well the sumi will develop in the next few years.

General Description of Kohaku


'Kohaku' is the term applied to a koi that has a white body with red markings. Kohaku is the first koi breed to be established by the Japanese, with breed stability being achieved in the 1890's.
Color
The shiro (white) base color of the body must be unblemished, thick, snowy, and even milky. The shiro must not exhibit any yellowish tint.
The hi (red) markings on the white body must be solid, deep, and evenly-colored throughout the entire body. The edges of these markings (also known as the 'kiwa') must be very defined, or as they say, 'sharp as a razor.'
The hi color may vary from koi to koi, but it should be of uniform hue within an individual koi.  Different koi exhibit different hues, from a deep persimmon orange to dark, purplish red.  This entire range is acceptable, although judges invariably have their own preferences.   
Pattern
The red markings on the body must be artistically balanced.  This means that they must not be confined to one side or one end of the koi only.  An equal distribution of shiro and hi is preferred, so in general a koi heavily marked with red or predominantly white in color is not desired. Red spots below the lateral line are not desired, and so are red marks that extend into the tail or the dorsal fin.
The pattern may be continuous or 'stepped', but the over-all effect of white and red balancing each other should be the ultimate consideration.  Many people prefer stepped koi and understandably so, since this pattern ensures red and white alternating with each other.  Nonetheless, there have been single-stepped (also known as 'ohmoyo') koi that have won championships for their 'total package' elegance.  
A white area separating the tail and the red marking nearest the tail is known as a tail stop, and is considered desirable. A red mark on the lips of a koi (also known as 'kuchibeni') is a 'plus' if it enhances the over-all package of the koi.
A good kohaku has a pattern on the head. The head pattern must extend slightly beyond the eyes but should not reach the nose or lips, leaving a white area in the front end of the head.  A fully red head (referred to as 'menkaburi') that makes the koi look 'hooded' is considered negative.  Nonetheless, some koi look good despite having it, so don't let it prevent you from buying a koi that you like.
A round patch of red on the head is considered nice.  If this red patch is the only marking on a white koi, then the koi is called a 'tancho kohaku', a highly-prized koi variety among the Japanese since it looks like their national bird.  If there are other markings on the body of the koi, then the round head patch makes it a 'maruten' kohaku.

The Koi Varieties

Koi Appreciation
Thanks to the ingenuity and dedication of Japanese master koi breeders, the world is now blessed with a diverse collection of koi breeds and varieties.  Present-day koi are so brilliantly colored that it's difficult to imagine all of them coming from the dull-colored fish grown for food in the mountains of Niigata, Japan centuries ago.   
To novice koi hobbyists, the flurry of Japanese terms corresponding to these various breeds can be daunting.  The advice commonly given is to get accustomed to the terms slowly and enjoy the learning process. The 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. 
    
 "Koi appreciation starts with the Kohaku and ends with the Kohaku."
   
Kohaku, which pertains to a white koi with red markings, is the first breed to be established by the Japanese.  Its simplicity, beauty, and availability make it the most popular and logical choice for a person buying his or her first koi.  Through the ensuing years this hobbyist may build up his collection by adding newer and more sophisticated varieties.  After having tried them all, however, this hobbyist will most likely 'rediscover' the Kohaku, finally experiencing first-hand what the cliche above really means.  But it doesn't end there, the cycle simply starts all over again.
    
Such is the hobby of koi keeping - a never-ending process of  'discovery' and 'rediscovery'.  Thirty years from now, our hobbyist might still be watching some of his or her original koi swimming in the pond after having owned many other varieties of these 'living jewels'.  If that will be the case, then he will have done things correctly, and can rightfully claim that he has, after all, achieved every koi keeper's dream.