Guide to Goromo Koi Varieties, Care, Size, Diet & Costs 2022 [Updated]
Koi carp are incredibly varied, beautiful fish that are popular around much of the world, so it may not come as a surprise that research has found that these fish have actually been bred for many thousands of years. Thanks to modern mtDNA sequencing, we now have proof to support the commonly held belief that koi are descendants of the common carp (Cyprinus carpio). In fact, this sequencing also found that most modern koi breeding practices originated in China and Japan around the 4th century and that the common carp, the koi’s direct descendant, originated in East Asia. This means that East Asia is technically the origin of koi, too – a previously oft-disputed idea.
This research also found that the eventual development of the koi began in China around 6,000 B.C. with the large-scale domestication and selective breeding of common carp to obtain different colored varieties and unique patterns. Without this tinkering, so to speak, long ago, we wouldn’t have the massive variety of patterns, colorations, and breeds of koi that can be found today.
As symbols of peace, goodwill, and alliances, these brightly colored koi were originally given to those with political and economic power. They were also historically viewed as symbols of wealth, placed in opulent water gardens visible to guests. The former is how koi initially made their way to Europe and, eventually, the Americas, becoming the beloved pets we know now rather than representations of power and wealth.
The Goromo (also known as Koromo) koi is a somewhat more recent breed, coming about in the 1950s as a result of breeding a Kohaku and an Asagi koi. They appear quite similarly to Kohaku with a white (Shiro) base overlayed with red (Hi), but thanks to their Asagi parentage will often have some blue-tinged coloration either within or edging around their red scales, giving the appearance of reticulation much like Asagi. Goromo koi can also be produced using Showa or Sanke parentage, but must always have an Asagi parent, as this guarantees the blue reticulation. However, most Goromo varieties are obtained using a Kohaku parent.
What Does Goromo Mean?
Koromo, as these koi are traditionally known, translates approximately to “clothed” or “robed” in Japanese, referencing the way their blue tint “robes” their Hi markings. Many English and American cultures refer to these koi as Goromo, which does not have a direct translation that can be found. We will use the two terms interchangeably throughout the article, as they are synonymous.
- Max; Suction Depth: 7 Ft
- Suction Hose Length: 16 Ft
- Discharge Hose Length: 8 Ft, Max; Flow Rate: 1300 Gph
Goromo Varieties & How to Identify Them
There are currently five fully recognized varieties of Koromo, though more are possible depending on exact parentage. Any pattern type recognized as Kohaku (such as Inazuma, Sandan, Tancho, and Marutan, among others) can also be observed in Goromo koi. Interestingly, true Koromo cannot be KinGinRin (metallic), though they can be Doitsu.
1) Ai Goromo
Ai Goromo are among one of the more common Goromo varieties. As “Ai” translates to “blue” or “indigo,” they possess blue shading within their Hi scales, rather than along the edges. If there is blue along scale edges, it is not typically considered an Ai Goromo. Commonly, the blue appears as a semi-circle within the scale. Oftentimes, the reticulation will form somewhat neat rows, largely along the back of the Koi much like in Asagi. There should not be any Ai present on the head in this variety.
2) Budo Goromo
The Budo Gomoro is actually a sub-variety of Ai Goromo, in which the blue (or sometimes black) clusters on the Hi, forming “grape” like clusters. In fact, Budo translates loosely to “grapes” in Japanese. This description is accentuated by the red sometimes showing through the blue, creating a purple-like appearance within the markings. This is not an incredibly common Goromo variety.
3) Goromo Sanke/Sanshoku
As might be excepted, a Goromo Sanke is one that has one Asagi and one Sanke or Sanshoku parent. These can possess virtually any of the pattern possibilities of Sanke, such as Tancho or Aka. These Goromo often have the typical blue reticulation, with the addition of some black (Sumi) anywhere on the body and/or head.
4) Goromo Showa
Goromo Showa are those that have an Asagi parent and a Showa parent. As a result, the Ai patterning may not be restricted to the Hi, and can exist elsewhere on the body.
5) Sumi Goromo
The rarest Goromo variety, Sumi Goromo have black reticulation rather than blue outlining the edges of the red scales. This Sumi patterning can be so thick that it seems to completely overwhelm the Hi, or it can be more subdued with the Hi showing through in places. Rather than occurring in neat rows like Ai Goromo, the reticulation of Sumi Goromo can appear more scattered and random.
How to Appreciate & Judge Goromo Koi
If you’re considering entering your Goromo koi into competitions, there are a number of things that you should familiarize yourself with. First and foremost, know that every competition is different and entirely dependent on the judges themselves – what may be considered appealing to one judge may not be to another. In Japan, judges also value fish based on their monetary value – a fish that costs more may result in an automatic bias in that fish’s favor, while if judged elsewhere patterning and proportions may come more into play. Try to know your audience beforehand, and research judges if you can.
General Guidelines for Judging Koi
Any type of koi should not have any abnormalities, such as missing fins, a misshapen mouth, or bruises (unless they were accidentally caused during transportation). They should also not have any parasites, ulcers, or other forms of illness.
Symmetry is also of great importance. The way that the Hi, Shiro, Ai, and, if applicable, Sumi, colors and patterns are arranged from front to back and side to side should be balanced and fairly symmetrical (not strictly symmetrical). If present, patterns that are unique are also favored. The fish should also have a proportional, symmetrical head with proportional, symmetrical fins, and a torpedo-shaped body. The skin/scales should be bright, healthy, and appear smooth.
Goromo Specific Judging Guidelines
Goromo koi with clearly defined “robing” are often judged more favorably. This means that many judges look for Ai coloration that is clearly defined within or along the edges of the Hi scales, and that carries down the koi’s back rather like a robe. Though Goromo can technically possess any patterning that is typical of Kohaku, Sanke, or Showa (depending in parentage), it is often most desired for them to have a stepped Hi patterning, meaning that there are multiple fairly symmetrical “patches” of Hi along the back of the koi. In all varieties of Koromo, it is generally a merit to have Hi present on the head (though not dominating it), while the presence of Ai on the head is judged negatively. Many judges prefer for Goromo to possess purely white fins, with the possible exception of a bit of Hi at the very base of the pectoral fins if it happens to somehow accentuate the fish.
If the Ai coloration extends outside of the Hi, this is viewed unfavorably, as is a “smudged” (asymmetrical or inconsistent) robe effect. Some judges greatly prefer for Ai to exist only within the scale, and not along the edges, particularly in Ai Goromo – this is where knowing your audience can be a huge help. Sumi Goromo can have Sumi present on the Hi on their head; a contrast to the other varieties, which should only possess white and red on their heads. Younger koi should have lighter Ai or Sumi coloration, as this will only grow darker as they age. Therefore, a young Koromo with fairly dark Ai or Sumi (even if it’s technically the “right” shade now) will be more likely to be judged unfavorably, as its Koromo effect will become too dark as it ages.
To learn more about judging criteria for specific koi varieties, check out our other koi guides here!
Keeping Goromo – Health, Growth & Diet
1) Goromo Water Quality
As with many of the more colorful koi varieties, Goromo koi will likely show some obvious signs if water quality is off. We use “obvious” in the literal sense, as you will often be able to visually tell by looking at your Goromo if the dietary or water quality parameters are off. For example, a diet too high in color enhancers, like spirulina, will cause any white portions on the Goromo to take on more of a yellow tint. It can also cause off-color orange spotting, which is undesirable in Goromo (they should possess red Hi, not orange Ki). Water that has a higher KH, or water hardness, and pH can result in Goromo with random black markings, which are not desired except in the case of Sumi Goromo, and even then the Sumi should exist within the confines of Hi markings.
Like most koi, Goromo needs are best met when water temperature is 50° F to 78° F (10° C-25° C), pH is between 7.5 & 8.5, dissolved oxygen is above 7 parts per million (ppm), salinity is kept very low between .05 & .15 parts per trillion (ppt), and there are only 75 to 100 ppm of total dissolved solids (TTDS), such as metals, minerals, salts, and sulfates.
2) Price of Goromo
Goromo koi can be fairly variable in pricing; they are somewhat of an up-and-coming breed in terms of popularity, if you will, but their possession of very unique blue coloring and their difficult breeding generally result in a higher price tag. Many juvenile Koromo can be found between 200 and 500 dollars or pounds, while others can be several thousand dollars depending on size and exact variety. For more information on this, scroll down to the “Average Cost” section of this article. If you find a particularly cheap Koromo, you may want to question this as cheaper fish may have come from poorly operated fish farms.
When purchasing, you should also factor in their water quality needs and the fact that proper aeration and filtration will be needed if these are not things already in place in your pond, and purchasing and maintaining these will, of course, add to overall costs.
3) Goromo Temperature
Though not incredibly well-studied, it seems that water temperature can play a hand in how koi look. Apparently, colder water lends to darker red or yellow coloration, while warmer waters can result in less vibrant hues over time. This could be related to changes in fish metabolism as temperatures shift, and resultantly how they absorb nutrients that impact coloration. One theory posed by the study linked above is that colder water slows the metabolism, so those nutrients stay in the fish’s system longer even though feeding occurs less frequently.
As mentioned previously, Goromo (and all koi) prefer water temperatures between 50° F to 78° F, or 10° C to 25° C. Additionally, make sure that your pond has varying depths to allow for your koi to swim to different depths to help naturally regulate their body temperature as needed.
4) Goromo Diet
A balanced diet is essential to the health of any koi. To help develop and maintain healthy coloration, colorful Goromo koi are often fed diets with color enhancers, such as those containing spirulina or krill, as well as those with ample (>30%) protein to aid in proper growth.
In particular, studies have found that feeds with high carotenoids result in a greater concentration of carotenoids in the skin, therefore leading to more vibrant coloring in red koi. If you have a Koromo, you may wish to amplify the blue coloration so it appears less grey or black – in this case, you’d utilize a food with supplemented astaxanthin, spirulina, and/or guanine, as these have been found to particularly amplify blue and purple coloration.
These color enhancers are of lesser importance if you don’t wish to show your fish at shows. Otherwise, though, the dietary needs of Goromo are much the same as most other koi.
How to Breed Goromo Koi
Breeding any koi can be tricky, but is especially so with rare koi that possess blue coloring, including Asagi, Shusui, and Goromo koi. Genetics are vastly variable and fickle, and the incredible amount of chance and nuance involved in coloration alone make it quite difficult to obtain exactly what you’re looking for with any koi breed, unless you’re a professional with an established line of Goromo. The addition of blue coloration that must, in most cases, exist within the Hi only adds to this difficulty and nuance.
If you have two Goromo parents, breeding is certainly easier but it will still be difficult to obtain exact traits (such as a Sumi Goromo) unless you are very experienced and know the history of both bloodlines.
What is the Cost of Goromo & Where to Buy Them?
Juvenile Koromo, as with any koi variety, are generally more affordable but can still be several hundred dollars or pounds. Adult Goromo, just as with any adult koi, will almost always be pricier and can range from several hundred to several thousand dollars. More common Goromo such as the standard Ai Goromo will tend to be on the lower end of the price range, while the rare Sumi Goromo can easily be several thousand dollars or pounds for an adult, and closer to 1,000 for a juvenile. More specific Goromo pattern types, such as Tancho, can be on the higher end, as well.
As with any koi, these prices are quite variable and depend on the seller and location, as well as whether or not bidding is allowed. We encourage you to check with your local breeder or a reputable online breeder for more exact information. Be sure to purchase Goromo, or koi of any type for that matter, only from reputable breeders. A reputable breeder should display their credentials on their site and/or in their shop. You can also determine whether or not a breeder is ethical and trustworthy by checking out koi forums – word of mouth travels fast, and koi owners are happy to provide info on both good and bad breeders.
Oftentimes, cheaper koi come from large fish farms or shady operations that don’t prioritize the health and wellbeing of the fish. Koi from non-reputable sources could be mistreated or have illnesses or parasites from being stocked with too many other fish or not being care for properly.