All Types Of Koi Fish | Koi Chart:

Koi are one of the most popular types of pond fish.
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There are many variations of how and where the scales appear on any given Doitsu Koi, but the most common are the scales running down the back. Doitsu scales are much larger and somewhat reflective as compared to the scales of a normally scaled Koi. A fully scaled normal Koi is referred to as Wagoi Koi (fully scaled) as compared to the partially scaled Koi is called a Doitsu Koi as discussed above. Sometimes these Doitsu scales can be difficult to see (as in the photo to the right). This is also the case depending on the color and pattern of any given Doitsu variety. Many times, however, in Doitsu Koi you can see a very distinct zipper-like pattern going right down the back of the fish. That "zipper" are the actual Doitsu scales all lined up and running down the back. It resembles a zipper. This is especially true when the scales are colored differently than the underlying skin color. So as far as scales types in Koi there are Doitsu (scaleless or partially scaled) and Wagoi (fully scaled), and in each there are varied scale patterns and types. With me so far? I hope so because I am about to make things even more confusing.
Various Types of Koi Fish and Their Color Pattern
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Where you buy koi carp will depend on what you ultimately want to achieve. If you simply want to keep healthy koi and are not overly concerned about the type, age or size of the fish, and are happy to begin with young fish that you can watch grow, you will have a wide range of options available to you. All Types Of Koi Fish | Koi Chart:
Photo provided by FlickrThe other types of Koi fish are-:
Photo provided by FlickrThis type of koi has sparkly, metallic scales. In my opinion, it has a truly gold color, unlike the goldfish which is more of an orange tone.
Photo provided by Flickr
There are 13 primary categories of Koi, and hundreds of varieties within those categories. The major named koi fish varieties include, but are not limited to the following (see descriptions below image):

Kohaku - White-skinned Koi, with a red pattern

Taisho Sanshoku (Sanke) - White-skinned Koi with a red and black pattern

Showa Sanshoku (Showa) - Black-skinned Koi with a red and white pattern

Tancho - Any koi with the only red being in a circle on its forehead. The fish can be a Tancho Showa, Tancho Sanke, or even Tancho Goshiki

Asagi - Koi with light blue scales on its top and red scales on its bottom

Shusui - The partially scaled version of an Asagi

Bekko - White, red, or yellow-skinned Koi with a black pattern

Utsurimono - Black Koi with a red, white, or yellow pattern

Goshiki - Mostly black Koi with red, white, brown and blue accents

Ogon - Koi that is one solid color; Can be regular or metallic; Known colors are red, orange, platinum, yellow and cream

Kin Gin Rin - Koi with shiny scales. The name translates into English as "Gold Silver Scales"; There are also Gin Rin versions of almost any other type of koi.

Kawarimono (Kawarigoi) - Miscellaneous types of Koi

Doitsu-goi - German Carp

Koromo - Koi with areas of blue-edged scales aligned neatly

Hikari-Moyomono - Koi with colored patterns over a metallic base, as well as koi in two metallic colours

Ghost Koi - "Hybrid" of Ogon and wild carp. Not Nishikigoi

Butterfly Koi - Long-finned version of all others. Not NishikigoiAlthough goldfish and koi carp are sometimes kept together in the same pond, and are related, the two types of fish are actually different species.Generally, the larger a koi is, the more expensive it will be, as someone else will have spent years and lots of money raising it to such an impressive size! Smaller koi are, as a general rule, cheaper than larger fish from the same bloodline or type.One of the main factors that dictate the price of koi carp of all types is the coloration of the fish. While different have dramatically different color variations, fish that are considered to be the best examples of their type and with the most impressive colors will invariably be the most expensive.