A Koi that is good for a show is typically one that has an eye-catching shape. This may often not be the kind of shape that gets to be Jumbo, nor the kind of shape that is good when big. When searching for a Koi to grow to a jumbo size, you should look for the proportions of the body, and head. The body should be long, and lean with a sense of power, and fairly good height to the backbone. The height of the backbone, as well as the profile of this height will largely identify the weight distribution of the body. What is meant by this is, if a Koi has a backbone profile that is very steep rising from the head, and then leveling out early, then the Koi will tend to have its body weight further forward than a Koi whose backbone rises in a more delicate manner, with its highest point being further back, around the front of the dorsal area. Aside from this, one advisable trait is to look for some width to the backbone, as a Koi with a decent physique, whose backbone appears prominent as if it is almost hollowed out somewhat either sides of its backbone, is an indication that the Koi is in a position of putting on a lot more weight. One big issue with Koi with a bad backbone shape is when they gain weight; it can usually distort the spine of the Koi, making it too deep in the body, and too flat down its back-line. Your only hope you have to stop such Koi becoming permanently misshapen is to breed to rid the Koi of eggs, but sadly, it usually doesn’t solve the issue. It is also appealing to buy a Koi with a nice smooth curve to the belly line, which blends very subtly into a deep tail tube that is both long, and strong. Be weary of a Koi whose tail tube looks thick because of it being short. The telltale sign of this is the rearward tip of the dorsal fin being too close to the bottom of the tail.
Now to the front : The head. As for the head of the Koi, it should be lengthy and wide, with the eyes well set apart, and plenty of distance in front of the eyes.
These days, When i hear people, especially dealers, state that bloodlines are of little importance when purchasing Koi, and that a Koi should be looked at solely on its own value. Such a train of thought is one I find very unusual. Given, there are no ‘pure’ bloodlines as we used to know them, but let’s face it, even many years ago, bloodlines was something of a unusual topic. Even in the old days, bloodlines were something made up by breeders partnering certain Koi, and then exploiting the qualities of specific offspring, and using them to breed the next generation of parent Koi. In reality, there is very little difference in how things are done now, as to how they were done in the ‘old days’ - this is clearly reflected in the way that one breeder’s Koi look very different from another breeder’s.
Understanding bloodlines
I as well as many believe bloodlines are key to selecting the right Koi from any given breeder. Sure, if you are searching for a Koi to take to the Koi show in the short term, then you can just buy the fish on ‘face value’,but if you’re purchasing a Koi with the intention of developing it to Jumbo, you simply have to have a superior understanding of its lineage. Lineage is like a form of history. If you don’t have any idea of the history, subsequently you have no idea of the future either. Regrettably, it’s not simply a matter of saying, "This Koi is of breeder ‘x’ bloodline", but a matter of understanding the mix of bloodlines that the specific breeder has used. What I mean by this is, you can’t solely say that a Koi has perhaps Dainichi male parents - you have to understand which lineage within Dainichi these male parents came from, as nowadays, their Kohaku for example, are very different from those of the old days. In fact, in the past few years, their lineage has transformed greatly with their ‘Gin x’ and ‘Junior x’ bloodlines. Knowledge the bloodlines of a Koi you are looking to buy gives you great comprehension into its future. If you have a good grasp of bloodlines, you will be able to identify qualities within the Koi in question. For example, you may belookingat two Koi in a bowl. One Koi might have inherited the Beni type from its mother, yet its brother or sister may well have the Beni type of its male parent. The same can be said of physique , skin, and Kiwa. This can perhaps make things a little complicated, but once you get the hang of it all, it can help you greatly in selecting a Koi that you can appreciate for many years to come. Best of its kind When looking for a Koi you intend to develop to Jumbo, the most important reason for knowing the bloodlines of a Koi you are proposing to buy is that the Koi you are looking at needs to be a good representation of how the best ‘Tategoi’ of that lineage should look. When you buy high-end Koi with a view to growing them to Jumbo, the requirements you and the breeder are searching for are a far cry from what you would look for if you were buying a Koi to take to a show in the short-term. If you want a "show Koi" then what you are searching for is a nice body shape, good strong thick colour, with good Kiwa, and tight Sashi, along with a good pattern. But, these considerations can work entirely the wrong way if you’re looking for a koi that might potentially be a future Grand Champion. In the latter case, the Koi won’t necessarily have a ‘good body shape’, of more importance is its bone composition, and head shape. In these factors, you are looking for signs of how the Koi is most likely to grow, and what kind of body shape and weight distribution it is likely to have when it gets big. In terms of colour, you will be searching for a colour that perhaps won’t fare well at a Koi show in the short term, but one that will improve slowly over the years, and peak in its beauty only when the Koi has developed to Jumbo. Purchasing a show Koi will undoubtedly lead to the Koi losing its colour condition premature in life, and being useless long before it has grown to Jumbo. A long-term pattern As far as pattern is concerned, you or the breeder will be seeking for something that will look attractive and imposing when the Koi is Jumbo, as compared to choosing a small Koi with a pattern that has to fit certain criteria that deem it appropriate for showing in the short-term. In terms of Kiwa, however good clear Kiwa is desirable for both short-term and long-term, knowledge will allow you to understand subtle variations in Kiwa that give you an clue of whether or not it will hold together only in the short-term, or keep long-term and increase in years to come. sign of very solid pattern/colour stability. Sashi… why is it important? Sashi is an fascinating point. A Koi needs to have Sashi in order to establish any kind of quality. If there is no Sashi, then the colour only exists in an uncovered area of each scale, which is also reflected in the Koi having a lack of ‘elasticity’ to its Beni, which can be observed by the Koi exposing white around the perimeters of the scales when it bends. However, Sashi that is too deep will fail to tighten up when the Koi gets old/big resulting in the Koi having untidy unrefined Sashi. An ideal with Tosai or Nisai, is for the Koi to have what seems to be one scale’s depth of Sashi, and for its greater edge to appear to reduce away to nothing, rather than being solid in colour with an apparent edge to where it stops. If anyone, even a breeder, tells you that two scales depth of Sashi will tighten, it will mean one of two things: 1) He just wants a rapid sale or 2) He will take a knife to it and make it shallower later. Skin quality Skin can be a little hard to judge if you are in the beginnings of your hobby.
Quite often, when a koi is bowled to show a buyer, they [the buyer] will express their appreciation and delight of a certain Koi’s skin quality. But, it is often the scenario that the Koi’s Beni is a little redder, which gives the buyer the belief that the skin is whiter… It’s a misleading "contrast thing" that you shouldn’t be fooled by! Good skin should look very thick, solid, and reflective in its visual appeal. Skin that looks a little grey/blue, or translucent is not such a safe bet. A slightly creamy appearance is also desired. The Sashi of the Koi also helps to give you an indication of the skin quality and this is by way of it feathering away to nothing as I mentioned before. The way Sashi looks is produced by the white scale and surface skin at the front of the pattern essentially hiding the red from showing through. Since the thickness of the scale/skin becomes thinner towards the tip of the scale, and thicker in the direction of the root, this is what makes the colour of the Sashi more notable near the surface, and much paler where the red scale becomes more embedded below a white one. So, Sashi is also a handy re-assurer of good skin quality. Be warned, if you looked for Koi using the above criteria, including most significantly the bloodline characteristics, then you will be constricting your search down to the one Koi that you basically can by no means ever ever afford. so my final word is if you don't have the money search for these quailtys within your price bracket.