Koi fish (Nishikigoi) are selectively bred ornamental carp recognized in 13 major variety classifications by the All Japan Nishikigoi Promotion Association. Each variety is defined by a specific combination of base color, pattern, and scale type — and within each variety, show-quality specimens are judged on criteria that go well beyond surface appearance.
Kohaku are white with red markings; Showa carry red and white on a black base; Sanke are white with both red and black. Beyond the Big Three, varieties like Ogon, Asagi, Utsuri, Chagoi, Bekko, and Kumonryu each follow their own genetic and evaluation standards. This guide covers all 13 recognized varieties, what distinguishes show-quality fish within each, and the role nutrition plays in color and pattern development.
The Different Koi Varieties and Patterns
The 13 main koi varieties recognized by the All Japan Nishikigoi Promotion Association don't just differ in color — they differ in genetics, breeding selection pressure, and what it takes to produce show-quality fish. Understanding variety-specific traits is the difference between buying a pond fish and building a collection. As you delve into the colorful world of koi, you'll discover an array of different koi species, each with its own story and charm.
What makes each koi variety unique, and how do you choose the perfect fish for your koi pond? Here is the ultimate guide of all the various types of koi.
Key Takeaways
- The 13 recognized Nishikigoi varieties and their precise identifying features
- How to read pattern quality markers: sashi, kiwa, and shiroji on Kohaku; sumi placement on Showa and Sanke
- What separates a pond fish from a show-quality specimen — and why nutrition is part of that answer
- How koi shows drive breeding decisions and bloodline demand
- A complete visual reference table for all 13 varieties
Click to jump to a koi variety to learn more
- Kohaku
- Taisho Sanke
- Showa
- Ogon
- Asagi
- Shusui
- Utsuri
- Bekko
- Tancho
- Koromo
- Chagoi
- Kumonryu
- Kikokuryu
The 13 Recognized Koi Varieties
Kohaku
Kohaku is the foundational variety of Nishikigoi — white-bodied with red (hi) markings — and remains the most contested class at serious shows. The variety appears simple. It is not. Because there are only two colors to evaluate, there is nowhere to hide: the quality of the white, the depth and consistency of the red, and the precision of every pattern edge are fully exposed under show lighting.
Identifying features: Pure white base (shiroji) with red markings on the body and head. No black. No metallic sheen. Pattern names describe the arrangement of hi: Nidan (two-step), Sandan (three-step), Yondan (four-step), Inazuma (lightning bolt), Maruten (isolated head spot with body pattern).
Show evaluation: Judges focus on three technical markers. Sashi is the leading edge of the hi pattern — it should be soft and gradual, not abrupt. Kiwa is the trailing edge — it must be sharp and cleanly defined. Shiroji (the white) must be bright and blemish-free; yellowing or grey tones are penalized. Hi should be deep and even in color, without fading toward the edges. Head hi that extends cleanly without reaching the nose tip or eyes is preferred.
Nutrition notes: Beta carotene is the primary dietary driver of hi intensity. A Kohaku fed a diet deficient in carotenoids will show faded, washed-out red regardless of genetics. The crisp white shiroji judges look for also depends on skin quality — which is tied to marine lipid intake, particularly DHA. The Kenzen Legacy Line was formulated with both outcomes in mind.
Taisho Sanke
Taisho Sanke (commonly called Sanke) is a three-color variety: white base with red and black (sumi) markings. It is one of the Big Three alongside Kohaku and Showa, and is the standard against which color separation and skin clarity are most rigorously judged.
Identifying features: White base with hi (red) and sumi (black). The critical distinction from Showa: Sanke have no sumi on the head. Sumi appears as distinct, solid islands on the body, typically above the lateral line. The base is white, not black.
Show evaluation: Clean color separation is the primary criterion. Sumi must appear as defined, solid black patches — never bleeding into the hi or shiroji. The head carries hi but must be free of sumi; any black on the head of a Sanke is a serious fault. White must be pure. Sumi that appears muddy, brown, or soft at the edges often indicates poor skin quality. Judges also evaluate body conformation and the overall balance of all three colors across the body.
Nutrition notes: Sumi stability in Sanke is sensitive to water quality and dietary mineral intake. Sumi that fades or turns brownish is often linked to deficiencies in fat-soluble vitamins or compromised water chemistry. A low-ash diet that supports clean water reduces one variable; high-quality protein provides the cellular substrate that pigment expression depends on.
Showa Sanshoku
Showa — formally Showa Sanshoku — carries the same three colors as Sanke (black, red, white) but is built on a black base, not white. This distinction is genetic, visual, and significant at the show bench. Showa sumi wraps the body with presence; on the best specimens, the black appears to hold the pattern together rather than decorate it.
Identifying features: Black (sumi) base with red and white wrapping around the body. Sumi appears on the head — this is expected and desirable, unlike Sanke. Motoguro (solid black at the base of the pectoral fins) is a defining feature of Showa and an important evaluation point.
Show evaluation: Judges assess depth and stability of sumi — it should be three-dimensional in appearance, not flat surface pigment. Sumi that wraps around the body rather than sitting on top of it scores higher. Pattern balance across all three colors matters: a Showa with too much black or too little white will not place well despite color quality. Strong motoguro is expected. Sumi on juveniles is often still developing; experienced judges evaluate potential as well as current presentation.
Nutrition notes: Black pigment expression in Showa is among the most nutritionally dependent of any variety. Marine protein — particularly herring meal — provides the amino acid profile that sumi development requires. Sumi that fades, fails to develop, or turns grey is frequently a diet and water quality issue. DHA from algae-based or marine sources also supports the skin health that underlies sumi clarity.
Ogon
Ogon are single-colored metallic koi — the variety is defined entirely by the uniformity and intensity of its reflective sheen. There is no pattern to evaluate, which means every square centimeter of the fish is under scrutiny. The most common are Yamabuki Ogon (gold) and Platinum Ogon (white/silver), with Orenji (orange) also well-established.
Identifying features: Single metallic color across the entire body. No pattern, no secondary color. Scales reflect light uniformly. Doitsu (scaleless or mirror-scaled) versions are common. Size and body shape are primary indicators of quality alongside sheen uniformity.
Show evaluation: Judges evaluate metallic luster uniformity above all else. A single dull patch, scale irregularity, or blemish will cost significant points — there is no pattern to draw attention away from skin imperfections. The sheen comes from iridophores (specialized reflective cells in the skin), and its quality is a direct indicator of long-term skin health. Body conformation also matters more in Ogon than in patterned varieties, since there is nothing else to evaluate.
Nutrition notes: Iridophore health — and therefore metallic luster — is directly tied to DHA intake and overall fat-soluble nutrient status. Ogon that develop dull or uneven sheen are frequently the result of diet rather than genetics. Marine lipids and high protein digestibility are the key dietary inputs for maintaining the luster that Ogon are judged on.
Asagi
Asagi are among the oldest Nishikigoi varieties, predating many of the color varieties that followed. The variety is defined by a blue reticulated (net-like) scale pattern on the dorsal surface and red (hi) on the belly, cheeks, and fin joints. At their best, Asagi have a restraint and depth that serious collectors find compelling precisely because they are not flashy.
Identifying features: Blue-grey dorsal surface with a reticulated fukurin (scale netting) pattern. Red hi along the belly, cheeks, and at the base of the fins. The blue should be even and consistent; the netting should be well-defined. No metallic sheen.
Show evaluation: Judges assess the regularity and symmetry of the fukurin — the netting pattern should be consistent across the full body, not patchy or fading toward the tail. The depth and evenness of the blue is critical; color inconsistency is a significant fault. The extent and quality of the hi is also evaluated — it should appear on the cheeks, belly, and fin joints in a balanced distribution. Asagi that are too red (hi rising above the lateral line onto the back) are considered overdeveloped.
Nutrition notes: The blue pigmentation in Asagi is particularly sensitive to water temperature fluctuations and mineral balance in the diet. Color inconsistency — patchy or faded blue — is often a combined water quality and nutritional issue rather than a genetic one. Stable mineral intake and consistent water chemistry are the primary levers.
Shusui
Shusui is the Doitsu (scaleless/mirror-scaled) version of Asagi. Developed in the early 20th century by crossing Asagi with German mirror carp, Shusui retains the blue back and red belly of Asagi but displays its coloration on skin rather than traditional scaled body, with a line of mirror scales along the dorsal and lateral lines.
Identifying features: Blue back, red belly and cheeks, mirror scales along the dorsal and lateral lines (not full body scaling). Skin between the scale lines is smooth. The scale line along the dorsal should be regular and straight — irregular scale placement is a fault.
Show evaluation: In addition to the blue/red color criteria from Asagi, Shusui are also judged on scale line regularity. Dorsal scale rows should be even, consistent in size, and follow a clean line from head to tail. Gaps or irregularities in the scale line are penalized. Color quality criteria are otherwise similar to Asagi.
Nutrition notes: As with Asagi, mineral balance and water stability support even blue expression. The exposed skin of Doitsu varieties is also more susceptible to environmental stress, making overall skin health nutrition (particularly DHA and fat-soluble vitamins) more significant than in fully-scaled varieties.
Utsuri
Utsuri (formally Utsurimono) are two-color koi with a black base and one secondary color: white (Shiro Utsuri), red (Hi Utsuri), or yellow (Ki Utsuri). They are frequently confused with Showa by newer keepers, but the distinction is clear once understood: Utsuri have only two colors, Showa have three.
Identifying features: Black base with white, red, or yellow markings. No third color. Sumi should appear on the head. Motoguro (black at the pectoral fin base) is present, as in Showa. The pattern wraps the body rather than sitting on the surface.
Shiro Utsuri (black + white) is the most common and most shown. Hi Utsuri (black + red) tends toward dramatic, high-contrast patterns. Ki Utsuri (black + yellow) is the rarest of the three and is prized by collectors specifically for that rarity.
Show evaluation: Sumi depth and body-wrapping coverage are the primary criteria — the same principles apply as in Showa. White (in Shiro Utsuri) must be clean and blemish-free. Motoguro should be solid and well-defined. Pattern balance — neither color dominating — is evaluated alongside color quality.
Nutrition notes: Same as Showa: marine protein for sumi development, marine lipids for skin quality underlying color clarity.
Bekko
Bekko are the two-color counterpart to Sanke: a solid base color (white, red, or yellow) with black (sumi) markings. The variety name refers to tortoiseshell, which the pattern suggests. Shiro Bekko (white base) is most common; Aka Bekko (red base) and Ki Bekko (yellow base) are less frequently seen.
Identifying features: Solid base color with sumi markings on the body. Unlike Sanke, there is no secondary pattern color — the only marking is black on the base. No sumi on the head. Pattern tends toward clean, distinct sumi islands.
Show evaluation: Cleanliness and definition of sumi islands is the primary criterion. The base color — whether white, red, or yellow — must be pure and consistent. Sumi should be solid black, clearly defined, and free of the bleeding or muddiness that indicates poor skin quality. As with Sanke, no sumi on the head.
Nutrition notes: Sumi quality in Bekko follows the same dietary dependencies as Sanke — mineral intake, fat-soluble vitamins, and overall diet quality directly affect the definition and stability of the black markings.
Tancho
Tancho is defined by a single red circle on the head and an otherwise white body — no other markings. The name references the Japanese red-crowned crane (Grus japonensis), the national bird of Japan, and the pattern is considered among the most refined in Nishikigoi. The variety is not a genetic classification in the same way others are; Tancho can occur across several base varieties (Tancho Kohaku, Tancho Sanke, Tancho Showa), but the Tancho class at shows is judged as a standalone category.
Identifying features: Solid white body with a single round red spot on the head, centered between the eyes. The spot should be round or oval, evenly colored, and positioned symmetrically. Any additional red on the body disqualifies a fish from the Tancho class.
Show evaluation: The head spot is everything. It must be round (not irregular or elongated), centered, deeply and evenly colored, and free of fading at the edges. The white body must be blemish-free. A technically perfect Tancho Kohaku with an off-center or irregular spot will not place; a fish with a flawless circle but yellowing white will not place either.
Nutrition notes: Hi quality requirements are the same as Kohaku — beta carotene intake directly affects the depth and evenness of the single head marking. Shiroji clarity depends on skin health, which is diet-dependent.
Koromo
Koromo ("robed" in Japanese) are Kohaku-based fish with an additional blue or dark overlay on the red scales, creating a layered, almost lace-like effect. The variety is the result of crossing Kohaku with Narumi Asagi, and the blue reticulation appears within the hi rather than on the white. Ai Goromo (blue-edged scales within the hi) is the most recognized form; Budo Goromo has a more solid purple-grape appearance within the red.
Identifying features: Kohaku base pattern (white with red) with blue or dark reticulation appearing within the hi markings only. The white base is unaffected. The depth of the blue overlay varies by individual and increases with age.
Show evaluation: The Kohaku criteria apply to the base pattern — hi quality, kiwa definition, shiroji clarity. Additionally, judges evaluate the consistency and depth of the koromo overlay within the hi. The overlay should be even across all red markings, not appearing in some hi patches but not others.
Nutrition notes: Both the hi quality and the blue overlay in Koromo are nutritionally sensitive. Diet that supports both carotenoid expression and mineral-dependent pigmentation is required to develop the full visual depth the variety is capable of.
Chagoi
Chagoi are single-color, non-metallic koi ranging from light tea-brown to deep olive-green. They are not a show variety in the competitive sense — Chagoi rarely win high placements because the evaluation criteria favor pattern complexity and color intensity that the variety doesn't offer. What Chagoi are known for is size, temperament, and their effect on pond dynamics.
Identifying features: Single color in the tea-to-olive-brown range (cha = tea in Japanese). No metallic sheen, no pattern. Scale reticulation (fukurin) is visible and desirable. Large body size is a hallmark of the variety.
Practical notes: Chagoi are widely regarded as the tamest koi variety — they hand-feed readily and have a calming effect on other fish in the pond, drawing shyer koi out. For keepers building a pond with a mix of varieties, a single Chagoi is often recommended as a social anchor. They also grow to exceptional sizes and are among the largest koi kept.
Nutrition notes: Given their size potential and growth rate, Chagoi benefit significantly from high-quality protein and digestible feeds. The Kenzen Legacy Line's marine protein base supports the sustained growth these fish are capable of.
Kumonryu
Kumonryu ("nine-crested dragon" in Japanese) are Doitsu koi with a black and white pattern that changes dramatically and unpredictably throughout the fish's life. The pattern is never fixed — black can recede or expand with season, temperature, and water chemistry changes. This instability is not a fault; it is considered part of the variety's character.
Identifying features: Black and white only, on a Doitsu (scaleless or mirror-scaled) body. The pattern shifts seasonally and can change significantly between summer and winter. No red. Mirror scales along the dorsal and lateral lines.
Show evaluation: Kumonryu are judged on the quality of the current pattern presentation — depth of black, clarity of white, and overall balance at the time of judging. Because the pattern changes, no two show entries from the same fish will look exactly alike.
Practical notes: Kumonryu keepers who are not familiar with the variety's pattern instability often mistake seasonal pattern shifts for disease or stress. This is normal physiology for the variety, not a problem to solve.
Nutrition notes: Overall skin health and water quality are the primary variables influencing pattern stability in Kumonryu. Low-ash feeds that support clean water and DHA-rich nutrition for skin quality are the relevant inputs.
Kikokuryu
Kikokuryu is the metallic version of Kumonryu — black and white (or black and platinum) on a Doitsu body with metallic luster. The variety combines the dynamic pattern instability of Kumonryu with the reflective sheen of the Ogon line. Beni Kikokuryu adds a red element, creating a three-color metallic variant.
Identifying features: Metallic platinum or silver body with black markings, Doitsu scaling. The metallic sheen distinguishes it immediately from Kumonryu. Pattern shifts seasonally as in Kumonryu.
Show evaluation: Metallic luster uniformity (as in Ogon) plus pattern balance (as in Kumonryu) are both evaluated. The sheen must be consistent — patchy or dull metallic areas are penalized. Pattern criteria parallel Kumonryu evaluation.
Nutrition notes: DHA and marine lipid intake are significant for maintaining the iridophore-driven metallic sheen. Diet quality directly affects whether the metallic component of the variety fully expresses.
Visual Reference: All 13 Koi Varieties at a Glance
| Variety | Base Color | Secondary Color(s) | Scale Type | Show Judging Focus | Nutrition Priority |
| Kohaku | White | Red (hi) | Traditional | Hi depth, sashi/kiwa edge definition, shiroji clarity |
Beta carotene, marine lipids |
| Taisho Sanke | White | Red + Black (sumi) | Traditional |
Color separation, no sumi on head, shiroji purity |
Balanced diet; mineral support for sumi stability |
| Showa | Black | Red + White | Traditional |
Sumi depth, motoguro, pattern balance, body coverage |
Marine protein for sumi development |
| Ogon | Metallic (single) | None | Traditional or Doitsu |
Luster uniformity, no blemish, body conformation |
DHA, marine lipids, skin-quality nutrition |
| Asagi | Blue-Grey | Red (belly/cheeks) | Traditional |
Fukurin symmetry, depth of blue, red extent |
Mineral balance, DHA for exposed skin |
| Shusui | Blue |
Red (belly/cheeks) |
Doitsu |
Scale line regularity + Asagi color criteria |
Mineral balance, DHA for exposed skin |
|
Shiro Utsuri |
Black |
White |
Traditional |
Sumi depth and wrap, motoguro, white clarity |
Marine protein, marine lipids |
|
Hi Utsuri |
Black |
Red |
Traditional |
Sumi depth and wrap, motoguro, hi depth |
Marine protein, beta carotene |
|
Ki Utsuri |
Black |
Yellow |
Traditional |
Sumi depth and wrap, motoguro, yellow evenness |
Marine protein, carotenoid support |
|
Shiro Bekko |
White |
Black (sumi) |
Traditional |
Sumi definition, white purity, no sumi on head |
Mineral intake, fat-soluble vitamins |
|
Tancho |
White |
Red (head only) |
Traditional |
Head spot roundness, centering, hi depth, shiroji |
Beta carotene, skin health nutrition |
|
Koromo |
White |
Red + Blue overlay within hi |
Traditional |
Kohaku criteria + overlay consistency across hi |
Carotenoid + mineral support |
|
Chagoi |
Brown/olive |
None |
Traditional |
Size, scale reticulation, body condition |
High-quality protein, digestibility |
|
Kumonryu |
Black + White |
None |
Doitsu |
Pattern balance at time of judging, skin clarity |
Low-ash feed, DHA |
|
Kikokuryu |
Metallic + Black |
None (or Red in Beni) |
Doitsu |
Luster uniformity + Kumonryu pattern criteria |
DHA, marine lipids |
Pattern Terminology Every Koi Keeper Should Know
PATTERN TERMINOLOGY
Understanding variety-specific criteria requires a working vocabulary. These terms appear throughout show evaluation and breeder descriptions.
Hi — Red pigmentation. Applies to Kohaku, Sanke, Showa, Tancho, and several other varieties. Quality factors include depth, consistency, and edge definition.
Sumi — Black pigmentation. Found in Sanke, Showa, Utsuri, Bekko, and Kumonryu. Show-quality sumi appears three-dimensional and fully developed, not flat or surface-level.
Shiroji — The white base color. Applies primarily to Kohaku and Sanke. Must be pure white without yellow or grey tones.
Sashi — The leading edge of a hi pattern on Kohaku. A good sashi is gradual and soft — the red blends gently into the white at the forward edge of each hi marking.
Kiwa — The trailing edge of a hi pattern on Kohaku. A good kiwa is sharp and precisely defined — the red ends cleanly against the white at the rear edge of each marking.
Fukurin — The reticulated (net-like) scale netting found on Asagi, Shusui, and Chagoi. Refers to the darker scale margins that create the net pattern when viewed from above.
Motoguro — Solid black pigmentation at the base of the pectoral fins. A defining feature of Showa and Utsuri; its presence and quality are evaluation points in both varieties.
Doitsu — The scaleless or mirror-scaled body type. Present in Shusui, Kumonryu, Kikokuryu, and Doitsu versions of many other varieties. Derived from German mirror carp crosses in the early 20th century.
Ginrin — A scale type, not a variety. Ginrin scales have a sparkling, reflective quality due to crystalline deposits in the scale. Any variety can have a Ginrin version; Ginrin Kohaku and Ginrin Showa are commonly shown.
How Koi Shows Plays a Role in Koi Breeding
Koi shows are not exhibitions. They are the mechanism by which breeding standards are set, refined, and propagated. Every fish that places at a major show — from regional club events to the All Japan — becomes a reference point. Breeders study the winners, identify which traits earned the placement, and make the next season's pairing decisions accordingly. The result is a feedback loop between show results, market demand, and genetic selection that has shaped modern Nishikigoi over more than a century.
Setting the Standard for Perfection
At koi shows, judges evaluate each fish based on strict criteria: pattern symmetry, color intensity, skin quality, body conformation, and presence. The koi that win aren’t just pretty — they’re prime genetic specimens. When a Kohaku takes home Grand Champion, that specific red-white pattern suddenly becomes the gold standard. After the show, breeders across the world aim to recreate it in the next generation.
Driving Breeding Decisions
Breeders closely follow show trends to decide which koi to pair. If metallic varieties like Kikokuryu or rare Tancho Showa start winning, breeders shift focus to refine those bloodlines. It’s not just about aesthetics — it’s strategic selection. Shows act like a live leaderboard, telling breeders what traits the market (and the judges) are hungry for.
Elevating Global Demand and Lineage Prestige
A koi that wins big at a prestigious show instantly gains value — not just in price, but in pedigree. Breeders proudly advertise the bloodline of their show winners, which drives demand and justifies higher prices for offspring. In short, koi shows act like the Oscars of the pond world — shaping taste, guiding breeding, and elevating what’s possible with each generation.
Color, Pattern, and the Role of Nutrition
Diet plays an equally direct role.
The red pigmentation in Kohaku hi and the metallic sheen of Ogon are both dependent on specific dietary inputs — beta carotene for color intensity, DHA from marine or algae-based sources for skin quality and reflective cell health, and high-quality protein for the cellular infrastructure that pigment expression depends on. A koi fed a low-quality diet with poor protein digestibility will show it in faded hi, dull whites, and metallic luster that fails to develop fully — no matter how good the water chemistry is. For keepers investing in show-quality fish, nutrition isn't a secondary consideration. The Kenzen Legacy Line was formulated specifically around these outcomes: year-round color support, hi enhancement, and the kind of skin clarity that holds up under show lighting.
Feed That Supports What You're Building
Pattern quality and color expression in every variety on this page are influenced by two variables the keeper controls: water chemistry and nutrition. Water quality is widely understood. The nutritional side is less consistently addressed.
Hi development in Kohaku and Tancho depends on dietary carotenoid intake — beta carotene specifically. A fish with strong genetics for hi will still produce faded, washed-out red on a diet that lacks adequate color-support inputs. Sumi development in Showa, Sanke, and Utsuri depends on protein quality and marine lipid intake; the cellular infrastructure that black pigment requires is built from high-quality amino acids, and DHA from marine or algae-based sources supports the skin health that underlies sumi clarity. Metallic luster in Ogon and Kikokuryu is generated by iridophores — reflective cells whose function is directly tied to fat-soluble nutrient status and DHA availability. A nutritionally deficient Ogon will show dull or uneven metallic sheen regardless of how clean the water is.
The Kenzen Legacy Line was formulated around these outcomes: marine protein (herring meal) for growth and sumi development, beta carotene for hi color enhancement, DHA from algae for skin quality and metallic luster, and a low-ash formula that keeps pond water supporting the fish rather than working against them.
Explore more from the Kenzen blog:
- The Legend of the Koi Dragon — The origin myth that made koi a symbol of perseverance across East Asian culture
- Kenzen Floating Koi Food — Year-round primary diet formulated for show-quality color and growth
- Kenzen Sinking Koi Food — Same formulation in a sinking pellet for bottom-feeding and shy koi
Frequently Asked Questions
How many types of koi are there?
The All Japan Nishikigoi Promotion Association recognizes 13 major variety classifications. Within those varieties, sub-types, scale variations (Doitsu, Ginrin), and metallic versions significantly expand the number of distinct forms a keeper will encounter.
What is the most popular koi variety?
Kohaku is the most widely kept and most contested variety at show level. Its simplicity makes it approachable for new keepers while its evaluation criteria make it one of the most technically demanding varieties for serious collectors. "Start with Kohaku, end with Kohaku" is a well-established principle in the hobby.
What is the difference between Showa and Sanke?
Both are three-color koi with red, white, and black. The key difference is the base color: Sanke has a white base, Showa has a black base. As a result, Showa sumi wraps the body with volume, and sumi on the head is expected. On Sanke, the head carries hi but never sumi. Looking at the head is the fastest way to distinguish the two.
What is the rarest koi variety?
Ki Utsuri (black and yellow) is the rarest among established varieties and is sought by collectors for that reason alone. A well-patterned Ki Utsuri with developed sumi is genuinely uncommon. Tancho Showa — a Showa with a single circular head spot — is also highly prized and difficult to produce to show standard.
What makes a koi show-quality?
The criteria vary by variety, but the consistent factors are: color depth and purity, pattern edge definition, skin quality (clarity, luster, absence of blemish), body conformation (straight spine, appropriate girth, well-proportioned fins), and overall presence. A show-quality koi meets the variety-specific technical criteria at a level that stands out under show lighting and close evaluation. Genetics set the ceiling; water quality and nutrition determine how close to that ceiling the fish develops.
Do koi varieties change color over time?
Yes, and predictably so. Sumi in Showa and Sanke continues to develop for years — fish shown at age two will look different at age five. Hi can deepen with age in Kohaku. Kumonryu and Kikokuryu change pattern seasonally and sometimes dramatically. Part of collecting Nishikigoi is understanding which changes are normal development and which indicate a health or water quality issue.
What koi variety is best for beginners?
Kohaku and Chagoi are both practical starting points. Kohaku for the learning value — keeping the variety teaches color evaluation skills that apply to everything else. Chagoi for temperament — they are the easiest koi to hand-train, grow to impressive size, and have a calming effect on other fish in the pond.
