Japanese Koi Terminology Every Koi Keeper Should Know

How Japanese koi descriptions fit together

A koi description usually contains several layers. Kohaku identifies a variety. Ginrin describes sparkling scales. Maruten describes the arrangement of red on the head and body. Nisai identifies an age class. “Excellent skin” evaluates the fish, while “future champion” predicts an outcome. These layers can appear in one sentence, but they are different kinds of information.

Japan’s JAS 0020:2022 standard provides an official vocabulary for Nishikigoi and variety descriptions used in transactions and competitions. It is a terminology standard, not a certificate that every fish bearing a recognised name is valuable. Nor does a variety name mean that the fish belongs to a separate biological species. [1]

This matters when reading a long listing. An elaborate name may describe several ordinary characteristics precisely, without telling you anything about their quality. Two Ginrin Maruten Kohaku can share the same descriptive label and differ greatly in body, skin, pattern and condition.

English spellings also vary. You will encounter Ginrin and Gin-Rin, Taisho Sanshoku and Taisho Sanke, and Koromo alongside names ending in Goromo. Spaces and hyphens often reflect editorial preference. Rather than treating every spelling difference as a new variety, compare the underlying description and, when available, the Japanese name or association illustration.

Some words have broader meanings in Japanese than their specialist use in koi keeping. A literal dictionary translation is therefore not always enough. Conversely, a memorable English explanation may be a hobbyist shorthand rather than an exact translation. “Living jewels” captures how people feel about Nishikigoi, but it should not be mistaken for a technical classification.

Nishikigoi koi and the meaning of a variety

Nishikigoi is the Japanese name for the ornamental carp discussed throughout this library. “Brocaded carp” is a useful English rendering, evoking coloured woven fabric. In everyday English, keepers usually shorten the name to koi.

A variety describes a recognisable combination of appearance traits. Some names concentrate on colour, others on markings, scale arrangement or metallic character. The name tells you what kind of appearance you are looking at; it does not tell you how successfully an individual fish expresses that appearance.

Think of variety identification and quality assessment as separate questions. First ask, “What is it?” Then ask, “How good is this example, and does it suit what I want?” A neatly patterned fish can still have a weak body. A fish with an unconventional pattern can still be the most enjoyable member of your pond.

Age sex and breeding roles

Tosai nisai and the importance of the hatch year

Tosai refers to the first-year age class, nisai to the second, and sansai to the third. Yonsai refers to the fourth. These terms are widely used around seasonal breeding and harvest cycles. They should not be read as precise birthday statements without checking how the seller records age.

For practical buying, a hatch year and the date of measurement are more informative than an age label alone. “Nisai, 48 cm” becomes much clearer when you know which spawning season produced the fish and when that length was recorded. The detailed age guide, KB-010, explains the calendar conventions and their limitations.

Jumbo tosai combines an age description with a size-related trade description. It does not establish a universally agreed minimum length, and it certainly does not guarantee a jumbo adult. Ask what the seller means by jumbo in that batch, then consider the fish’s actual measurements and development history.

Male female and oyagoi

Male and female may be expressed as osu and mesu. Listings often use the English words instead, which is perfectly adequate. Whatever language is used, ask whether sex is confirmed or estimated. A confident-looking label does not make a difficult juvenile sex assessment certain.

Oyagoi means parent or breeding koi. It describes a role in a breeding programme. It is not an age class, and it does not automatically mean a fish is a successful show specimen. A breeder may value a parent for traits it transmits even when its own appearance is less suitable for competition.

When someone names an oyagoi behind a fish, clarify the relationship. Are they identifying an actual parent of that batch, describing a broader line, or referring to a famous ancestor? Those claims are not interchangeable. Written provenance is especially useful when breeding information contributes substantially to the price.

The colour words you will hear most often

Hi and beni

Hi and beni both concern red. Hi commonly appears in descriptions of red markings and in names such as Hi Utsuri. Beni is frequently used when discussing the character and quality of red pigmentation, particularly in Gosanke. Usage overlaps; they are not two neatly separated colours with universally fixed numerical boundaries.

If a dealer says a fish has “good beni,” the next question is what makes it good. Are they referring to consistency across the red areas, a pleasing hue, a substantial visual appearance, or confidence in its future stability? Asking for the observation behind the adjective teaches you more than accepting the adjective alone.

Hiban means a red pattern plate or patch. It is useful when discussing one element rather than the entire red pattern. A three-step Kohaku has separate red elements; a keeper might discuss the first hiban on the head and then the following body elements. The association’s Kohaku guide connects these red patches with stepped and other pattern descriptions. [2]

Red that appears darker in a photograph is not automatically better. Exposure, white balance, reflection and editing all change perceived colour. Compare the fish in a clear recent video or in person, and avoid trying to judge the long-term quality of beni from one highly saturated image.

Shiroji

Shiroji refers to the white ground or white areas of a koi. It names something you can locate on the fish. “Excellent shiroji” adds an assessment of that white, which requires a closer look.

On a Kohaku, the white spaces help separate the red pattern. If you look only at the red shapes, you can miss how the white makes the composition readable. For learning, trace the white spaces around each red element as carefully as you trace the red itself.

White is also easily misrepresented by surroundings. A blue bowl, green pond water, overhead shade and bright reflections can all affect its appearance in photographs. A yellowish image does not establish permanent poor white, and an almost glowing white image does not establish exceptional skin.

Sumi

Sumi is the principal word for black pigmentation or black markings. It is particularly important in Sanke, Showa and Utsuri discussions. Like beni, it can appear in both straightforward description and qualitative commentary.

The association describes Sanke in terms of black markings added to a red-and-white appearance, while its Showa explanation emphasises the different organisation of black around the body. [3, 4] That distinction is more informative than simply counting colours. Both varieties can show red, white and black, but the black participates in the overall design differently.

“The sumi will improve” is a prediction. Ask which area the speaker means and what they expect to change. A seller should be able to point to a particular marking or development feature instead of relying on a general promise that the fish will become better.

Ki kin gin and hikari

Ki refers to yellow. Kin and gin refer to gold and silver in the relevant names and descriptions. Hikari concerns shining or metallic character. These words help you interpret labels, but their presence does not replace a visual assessment.

For example, yellow colour and metallic shine are separate properties. A yellow non-metallic fish and a yellow metallic fish should not be treated as the same variety merely because both appear yellow. Similarly, a silver-looking reflection in a photograph is not enough to classify a fish as metallic.

Scales sparkle and metallic skin

Wagoi and Doitsu

Wagoi is used for normally scaled koi. Doitsu describes koi with greatly reduced scalation, commonly leaving prominent scales in particular rows or positions. The association explains the connection with German carp ancestry; Doitsu does not mean that the individual fish was bred in Germany. [5]

A Doitsu Kohaku and a normally scaled Kohaku share the red-and-white variety appearance, while presenting it through different scale arrangements. Their names contain both pieces of information. This is why Doitsu is often a modifier rather than a complete answer to “What variety is it?”

When assessing a Doitsu koi, look at the actual remaining scales. Ask whether their arrangement is orderly and whether it supports the appearance of the fish. Do not assume that reduced scalation means there is nothing about scales to evaluate. Large remaining scales can be very conspicuous.

Aragoke is a term you may hear for conspicuously large armour-like scales. It is a useful description, but it does not mean every large scale is abnormal. Context matters, especially in reduced-scale fish. Kokenami concerns scale arrangement; the practical task is to examine the rows rather than admire the vocabulary. [11]

Ginrin and Kinginrin

Ginrin refers to the sparkling appearance of scales. Kinginrin is also used for the golden and silvery reflective scale characteristic. The association presents Ginrin across multiple underlying varieties. [6]

A Ginrin Kohaku remains a Kohaku with a particular reflective scale feature. Those flashes of light are different from the broader metallic appearance described by hikari terminology. A fish can sparkle attractively without belonging to a metallic variety.

Try watching a Ginrin koi as it moves slowly through even light. Individual scales should become easier to distinguish from glare on the water surface. A single still photograph may exaggerate a few reflections or fail to show others, making it a poor basis for comparing the distribution of sparkle.

You may encounter Ginrin A and Ginrin B in classification systems. In the JAS vocabulary, A concerns Ginrin Gosanke and B concerns other underlying varieties. The letters are not grades meaning premium and second-rate. Check the particular show’s class definitions before applying those labels elsewhere. [1]

Fukurin and general lustre

Fukurin describes an appearance involving the skin around the scales, often producing a pronounced mesh-like effect. It should not be confused with the dark pigmentation pattern that creates reticulation on an Asagi. Two surfaces may both look netted while the visible effect comes from different features. [11]

Tsuya refers to lustre. Keepers also use terms such as teri when discussing sheen. These are evaluations of appearance, not laboratory measurements supplied by a name. Ask to see the effect in consistent lighting and across the fish, rather than accepting one bright highlight as proof.

Healthy-looking shine is also not a health certificate. This article concerns appearance vocabulary. Buying decisions still require appropriate health history and biosecurity, which are covered separately in the introduction and quarantine articles.

Finding your way around variety names

Gosanke and the three familiar names

Gosanke is the familiar collective name for Kohaku, Taisho Sanke and Showa Sanshoku. Kohaku is red and white. Sanke and Showa both involve red, white and black, but they are not interchangeable names for any three-coloured koi. [2–4]

For Sanke and Showa, examine the organisation of black together with the head, body and fins. The association contrasts Sanke’s black accents with Showa’s more continuous, wrapping black pattern. Head markings and pectoral markings can provide useful clues, but one isolated spot should not become your entire identification method.

Sanshoku means three colours. Taisho and Showa connect the established names to Japanese eras. They do not mean that a living fish was born during those eras. This is another example of why literal fragments need the context of an established variety name.

Utsuri and Bekko

Shiro Utsuri combines black and white; Hi Utsuri combines black and red; Ki Utsuri combines black and yellow. Bekko names also include white, red or yellow forms, but the black marking arrangement belongs to a different appearance category. [1]

For a beginner, the useful lesson is to compare the pattern organisation, not just the colour list. “Black and white” narrows the possibilities without necessarily identifying the variety. Ask the seller to explain the placement and character of black that led to their classification.

Asagi Shusui Goshiki Koromo and Kujaku

Asagi has a blue-toned reticulated appearance on the scaled body, with red typically associated with lower areas and fins. Shusui is closely connected to that appearance but has Doitsu scalation. These two names give a good introduction to how scale arrangement can reshape a related colour design. [7, 8]

Goshiki and Koromo require attention to where the darker scale-related appearance occurs. Goshiki includes reticulation in the ground appearance, whereas Koromo is especially associated with darker edging or overlay within the coloured pattern areas. The association’s descriptions distinguish them on that basis. [9, 10]

You may see Ai Goromo and Budo Goromo. These names describe different Koromo appearances; budo evokes grapes. Do not expect every fish sold under a name to reproduce an ideal illustration exactly. A young individual, an unusual example and an unclear photograph can all make classification less obvious.

Kujaku combines metallic character with a netted scale appearance and coloured markings. [12] It demonstrates why “has a mesh pattern” alone is insufficient: Asagi, Goshiki and Kujaku can all invite that description, while differing in other essential characteristics.

Metallic groups and the catchall category

Hikarimuji concerns single-coloured metallic appearances. Hikarimoyo concerns patterned metallic appearances, while Hikari Utsuri covers metallic appearances associated with the black-based Utsuri and Showa group. These are classification concepts, and shows may organise their entry classes differently. [1]

Kawarimono and Kawarigoi are names you will encounter for a broad assortment of appearances outside the more familiar groups. Treat them as classification language, not a verdict that a fish is inferior. A category containing diverse koi does not tell you whether an individual has excellent conformation or is a pleasure to keep.

This is enough terminology to navigate the variety map. The dedicated variety articles provide the detailed identification, selection and development discussions. Trying to turn this glossary into every variety guide would obscure the main purpose: understanding what a description means.

Pattern words and the shapes they describe

Nidan sandan and inazuma

Nidan describes a two-step pattern; sandan describes three steps. You may also encounter yondan for four and godan for five. “Steps” are separate pattern elements seen along the body, not a grading ladder in which a larger number automatically means a better fish.

The association also uses inazuma for a lightning-like pattern. [2] Imagine tracing a connected, changing line of red rather than counting isolated islands. The description gives you a visual route through the pattern, but it does not establish that the route is balanced or attractive on that particular body.

On a small fish, pattern elements can look proportionally different from the same elements on a larger body. A useful buying question is whether the seller likes the current arrangement or expects it to become better balanced with growth. Their answer should remain an explanation of expectation, not a guarantee.

Tancho and maruten

Tancho is associated with a distinct head marking, conventionally round and red in the familiar Tancho descriptions. In Tancho Kohaku, the red is confined to the head. Tancho Sanke and Tancho Showa may have black on the body; the important distinction is the absence of additional body red. [13]

Maruten describes a separate head red marking together with other red markings on the body. A round head mark alone therefore does not settle whether the fish should be described as Tancho or Maruten. You must inspect the rest of the red pattern.

The distinction becomes easy with two imagined Kohaku. One has a head circle and an otherwise white body. The other has a similar head circle plus two body patches. The first fits the familiar Tancho Kohaku description; the second has a Maruten arrangement. Neither label tells you which fish has the stronger body or skin.

Head and fin markings

Kuchibeni concerns red on the lips. Menkaburi describes a head heavily covered by red. Menware concerns a splitting black head pattern associated with Showa and Utsuri discussions. These words direct your eye to different parts of the head; they are not interchangeable compliments.

Motoguro describes black at the bases of the pectoral fins. Motoaka concerns red in that location. Tejima describes black stripes in the fins. [11] When a dealer mentions one of these features, ask them to point it out in the video. Looking at both fins and their relationship to the body is more useful than hunting for a marking on only one side.

For all these terms, separate presence from quality. A feature may be present without being balanced, and balance itself must be interpreted in relation to the variety and individual fish. Memorising “motoguro is desirable” without understanding context can turn a useful word into an unreliable purchasing rule.

The end of the pattern near the tail

The tail end of a pattern deserves attention because it affects how the composition finishes. English glossaries are not entirely consistent about odome: some use it for the final marking, while others discuss the white separation before the tail under that name. Ojime also appears for the gap. [11]

Rather than argue over a word during a purchase, clarify the visible feature. Ask, “Do you mean the last red patch, or the white space between that patch and the tail?” A marked photograph resolves the ambiguity immediately. This habit is useful whenever specialist vocabulary has variable trade usage.

Understanding sashi and kiwa

These are two of the most useful terms in koi assessment, and two of the easiest to misunderstand. Sashi concerns the leading edge of a coloured pattern element, toward the head. Kiwa concerns its trailing edge, toward the tail. They help you discuss the boundary of a pattern rather than its general shape. [11]

On a scaled red-and-white koi, the way scales overlap can make the leading boundary appear softer. That visible transition is the context in which sashi is commonly discussed. The trailing boundary presents a different view of the colour edge. Learning which direction you are examining prevents you from calling every soft boundary “bad kiwa.”

Start with one hiban on a clear overhead image. Find the end facing the head and the end facing the tail. Then compare those boundaries with another hiban on the same fish. This is a better first exercise than attempting to assign a quality grade from a distant pond view.

The terms identify boundaries; they do not, by themselves, explain why a boundary looks a particular way. Scale overlap, development, photography and the actual condition of the coloured area all deserve consideration. If the seller says the sashi is “coming together,” ask what has changed since the previous photograph and which sections remain unresolved.

Breeder development notes illustrate this distinction between present appearance and expectation. Byer Koi Farm’s discussion of selected young Kohaku comments on edges that are not yet refined and on which fish are worth watching. [14] That is an assessment of particular fish at a particular stage, not a rule that every unrefined edge will improve.

Avoid the equally simplistic opposite rule that every soft edge means the fish has no future. A close image, developmental context and a specific explanation are needed. If the distinction is still unclear, ask the breeder or dealer to show two comparable fish and explain what makes one boundary more convincing.

Quality language and its limits

Body conformation

Conformation describes body structure and proportions. It concerns the way the head, shoulders, trunk, tail region and fins fit together. The association’s judging guidance gives body shape a central role rather than treating a koi as a flat collection of coloured patches. [15]

This helps explain why a memorable pattern is not a complete quality assessment. A beautiful arrangement cannot be evaluated independently of the body carrying it. For your own viewing, spend a moment looking at the outline before analysing colour. In video, examine whether the fish appears balanced as it moves and whether both sides can be seen clearly.

“Powerful body” and “good frame” are evaluations, not precise measurement records. Ask what the speaker is seeing. Length alone does not define conformation, and a broad appearance in a photograph can be affected by angle. A recent overhead image and natural swimming video give more context.

Finish and current condition

Finish refers to how fully an appearance presents at the time of assessment. A fish described as well finished may show a coherent, clear current presentation. The word does not mean that it has stopped growing or that its appearance can never change.

The association’s examination guidance considers quality, finish and pattern alongside body shape. [15] That framework is useful because it keeps current presentation separate from a forecast. A fish may be attractive now without being the seller’s strongest long-term growth candidate. Another may have development interest while lacking the completeness preferred for an immediate show.

Neither purpose is inherently the correct one for every hobbyist. If you want a koi to enjoy in your pond today, current appearance matters. If you enjoy following development, you may accept uncertainty. State your goal so that words such as finished or promising are interpreted against the right objective.

Shimi and unwanted black spots

Shimi is used for small unwanted black spots, particularly where they interrupt the intended appearance of a red-and-white fish. [11] The word describes an appearance concern. It does not establish the cause of every dark spot or distinguish pigmentation from a lesion in an unclear photograph.

If a spot is new or looks abnormal, do not let a cosmetic label substitute for a health assessment. Nor should recognising the term encourage scraping, cutting or other amateur attempts to alter the fish. Ask for a clear view and appropriate advice. A vocabulary article is not a treatment protocol.

Breeder and sales language that needs careful questions

Tategoi

Tategoi concerns perceived future potential. It is one of the most attractive words in koi sales because it invites you to imagine a better fish than the one presently in front of you. Breeder-led material such as Kodama’s tategoi study resources treats it as a subject for following development. [16]

The important limitation is that potential is a judgment. The word alone does not provide a standardised score, a promised adult size or an assured show result. Two sellers can use it with different levels of selectivity.

Ask why this individual is considered promising. Perhaps the seller values its body, a particular aspect of pigment, or its performance relative to siblings. Ask what might go wrong as well. A useful discussion of potential should include uncertainty, because the future fish cannot be inspected today.

You may also hear tateshita when discussing fish released from a breeder’s retained selections. Trade explanations vary and can become overly dismissive. Do not infer from the label alone that a fish cannot improve or cannot be an excellent pond koi. Ask what the breeder retained, what they released and why this fish suits your purpose.

Selection harvest and keeping a fish with the breeder

Senbetsu concerns selection or sorting. In a breeding programme, selection serves the breeder’s objectives at a particular stage. It should not be imagined as a universal certification process that assigns the same quality level across every farm.

Ikeage refers to bringing fish up from a pond, commonly discussed around harvest. The excitement of a harvest describes an event, not a complete account of the fish’s subsequent care or health status. A harvest photograph should not be read as evidence that quarantine has been completed.

Azukari is commonly used when a fish remains in another party’s care, often with a breeder for further raising. If an arrangement is offered, translate the attractive label into a written agreement. Identify the period of care, fees, ownership, reporting, collection or shipping arrangements, and what happens if the fish is injured, dies or develops differently from expectations.

These practical questions matter more than whether the arrangement has an elegant Japanese name. Do not assume that two farms use identical terms or provide identical responsibilities. The vocabulary introduces the conversation; the agreement determines what you are buying.

Bloodline breeder and provenance

A breeder name identifies a source, while a bloodline claim concerns ancestry. Neither word automatically describes the quality of every fish associated with it. A successful farm produces individuals with different characteristics and different outcomes.

For a Malaysian buyer receiving imported koi, keep the descriptive name alongside ordinary records: supplier, stated breeder, hatch year, purchase date, measurements and photographs. If the fish is advertised through several parties, clarify who is making the provenance claim and what documentation accompanies it.

“Japanese koi” and “Doitsu koi” answer different questions. The first can concern origin; the second concerns scale characteristics. A Doitsu fish can be bred in Japan, and normally scaled Nishikigoi can be bred elsewhere. Mixing these layers creates avoidable confusion.

Show words and what an award really says

Benching is the entry process through which a show records and places fish in the relevant categories, including size and variety classifications under its rules. It is not the same process as selecting the winner. The National Koi Show’s exhibitor information distinguishes benching from the later announcement of awards. [17]

Grand Champion is an award within a particular competition. Reserve Grand Champion and other champion titles also depend on that event’s structure. Young Champion and Baby Champion should not be assumed to reproduce tosai and nisai age classes. Read the organiser’s definitions instead of guessing from the ordinary English words.

An award is valuable information about a result on a particular occasion. Record the show, year, category and fish identification. “Champion bloodline,” “show quality” and “Grand Champion” are not equivalent claims: ancestry, a sales assessment and a documented result describe different things.

You will also encounter organisational names and abbreviations, including ZNA and the All Japan Nishikigoi Promotion Association. When entering a show, use the organiser’s current documents. A general glossary cannot establish the exact class boundaries, eligibility conditions or award arrangements for every event.

Reading three example koi descriptions

A Ginrin Maruten Kohaku

Suppose a listing reads, “Nisai Ginrin Maruten Kohaku, female, 46 cm, excellent beni.” These are illustrative words, not a real offer.

Kohaku identifies the red-and-white variety. Ginrin describes the sparkling scale characteristic. Maruten tells you to expect a separate head marking plus red elsewhere on the body. Nisai identifies the age class. Female is a sex claim, and 46 cm is a measurement that should have a date. “Excellent beni” is the seller’s evaluation.

Your questions can now be specific. Which hatch year? Is sex confirmed? When was it measured? Can you see the sparkle in a recent video? What does the seller consider excellent about the red? You have moved from reacting to a prestigious-sounding sentence to understanding its contents.

A Doitsu Showa with development interest

Consider, “Tosai Doitsu Showa, sumi still developing, tategoi potential.” Showa identifies the underlying appearance category; Doitsu describes reduced scalation. Tosai concerns age. The remaining phrases discuss present incompleteness and expected future potential.

Ask the seller to identify the black areas they expect to change and explain the basis for their assessment. Request a current image rather than relying on a sibling photograph or a mature parent. Decide whether you actually enjoy uncertain development. A fish bought for that purpose should not later be judged as though its finished appearance had been guaranteed.

A Tancho offered for further raising

Finally, imagine “Tancho Kohaku available with azukari.” Tancho Kohaku describes the familiar head-only red arrangement on a white fish. Azukari concerns the proposed care arrangement. It does not improve the head marking, establish sex or define a promised growth rate.

Evaluate the fish and the arrangement separately. A fish you like may come with unsuitable terms. A well-organised care service may be offered for a fish you would not otherwise choose. Separating those decisions helps prevent the experience surrounding a purchase from overshadowing the animal itself.

A compact alphabetical reference

Use this section to find a word quickly after reading the explanations. Definitions are deliberately brief; the preceding sections provide the qualifications.

Aragoke — conspicuous large armour-like scales.

Asagi — a blue-toned reticulated scaled appearance with associated red markings.

Azukari — a care arrangement in which a fish remains with another party.

Beni — red pigmentation, often discussed in terms of its character and quality.

Benching — the show entry and classification process.

Doitsu — reduced scalation, not a statement of current country of origin.

Finish — the completeness of appearance at the time of assessment.

Fukurin — a visible effect involving skin around scales.

Ginrin — the sparkling scale characteristic.

Gosanke — Kohaku, Sanke and Showa considered collectively.

Hi — red, especially in marking descriptions and established names.

Hiban — an individual red patch or pattern plate.

Hikari — shining or metallic character in the relevant descriptions.

Ikeage — bringing fish up from a pond, commonly at harvest.

Inazuma — a lightning-like pattern arrangement.

Jumbo tosai — a size-related trade description for first-year-class koi.

Kawarigoi — a broad classification covering diverse appearances.

Ki — yellow.

Kin and gin — gold and silver in relevant names and descriptions.

Kiwa — the trailing boundary of a pattern element.

Kohaku — red-and-white Nishikigoi.

Kokenami — scale arrangement.

Koromo — an appearance associated with darker overlay or edging on coloured scales.

Kuchibeni — red on the lips.

Maruten — a separate head red marking with additional body red.

Menkaburi — substantial red coverage of the head.

Menware — a splitting black head pattern in relevant varieties.

Mesu and osu — female and male.

Motoaka — red at the pectoral fin bases.

Motoguro — black at the pectoral fin bases.

Nidan and sandan — two-step and three-step pattern descriptions.

Nisai — the second-year age class.

Nishikigoi — ornamental brocaded carp, commonly called koi in English.

Odome — tail-end pattern terminology whose trade definitions require clarification.

Oyagoi — parent or breeding koi.

Sanke — the familiar shortened name for Taisho Sanke.

Sansai — the third-year age class.

Sashi — the leading boundary of a pattern element.

Senbetsu — selection or sorting.

Shimi — small unwanted black pigmentation spots in appearance discussions.

Shiroji — the white ground or white areas.

Shusui — an Asagi-related appearance with Doitsu scalation.

Sumi — black pigmentation or black markings.

Tancho — the distinct head-mark arrangement in the relevant variety description.

Tategoi — a judgment of future potential.

Tejima — black stripes in the fins.

Tosai — the first-year age class.

Tsuya — lustre.

Wagoi — normally scaled koi.

Yonsai — the fourth-year age class.

Learning the words without losing sight of the fish

Begin with photographs of fish whose identification is clear. Choose one variety and practise finding the white ground, red patches and their boundaries. Add one new term at a time. If you cannot point to a feature, reread its explanation rather than simply memorising the spelling.

Keep short notes with dated photographs of your own koi. “The second red patch has a softer leading boundary” is a useful observation, even before you remember sashi. Later, the specialist term gives you a concise way to discuss the same observation with someone else.

For a website or sales catalogue, pair unfamiliar words with plain English on first use. Readers should not have to know the glossary before they can understand a listing. A description such as “Maruten, with a separate red head marking and additional body red” serves beginners without inconveniencing experienced keepers.

The most useful question remains simple: “Could you show me what you mean?” A breeder pointing to a specific scale row or pattern boundary can teach you more in a minute than a paragraph of unexplained praise.

Frequently asked questions

Do I need to memorise every variety name

No. Learn the main groups and the terms that explain fish you own or are considering. You can look up uncommon names when needed. Understanding how descriptions are assembled is more useful than reciting a long list without recognising the features.

Are hi and beni completely different colours

No fixed universal colour boundary separates their everyday koi usage. Both concern red, with different emphasis in particular descriptions. Ask what the speaker is evaluating rather than assuming one word automatically means a superior shade.

Is a Ginrin koi necessarily metallic

No. Sparkling scales and the metallic character described through hikari terminology are distinct features. Examine the underlying variety and the actual appearance rather than treating any bright reflection as the same characteristic.

Does tategoi mean the fish will become a champion

No. It expresses perceived future potential. The reasons behind that assessment, the seller’s selectivity and the uncertainty of development all matter. A documented show result and a future prediction are different kinds of claim.

Is Tancho the same as a round red head mark

The rest of the red pattern matters. In the familiar Tancho Kohaku arrangement, red is restricted to the head. A similar head marking with additional red on the body is described as Maruten. Tancho Sanke and Showa can retain black body markings.

Should a beginner avoid a fish with an unfamiliar name

Not solely because of the name. Ask for a clear explanation of its appearance and assess whether it suits your pond and preferences. A familiar label is no protection against a poor purchase, while an unfamiliar variety may be easy to appreciate once explained.