Some koi are worth thousands of pounds, but unfortunately not all. So from looking at tosai could you tell its worth a year on?

When you think tategoi most people think of young fish with the potential to improve and increase in monetary value. But koi as old as seven can still be classed as tategoi. So how are the tategoi chosen and what exactly happens to the ones who don’t quite make the grade?

The number one ‘tateshita’ is still a very high quality koi but the breeder cannot grow on everything and must draw the line somewhere

If you translate tategoi from Japanese to English there is not a single word that can explain its meaning. It is a number of words all rolled into one but the basic gist is ‘a koi that is showing signs of top potential for the future’.

The Word to make note of in this translation is ‘potential’. Just because a koi is labelled ‘tategoi’ it does not guarantee future greatness. As the koi grows the chances of a tategoi fulfilling its potential becomes greater, after all, three-year-old (sansai) tategoi still has potential to maybe improve further but has already fulfilled quite a lot. Let me try and explain it by starting with tategoi tosai (one-year-old koi).


Small tategoi tosai (under 25cm) are probably the hardest to select but usually the most available. The reason for this is that every breeder has to grow on many small koi to nisai, as it is not possible to ascertain whether they are male or female at this young age. Therein lies their dilemma, they only want females to grow on (unless for broodstock), but have to select the koi purely on the basis of quality and pattern and hope they are picking a high percentage of females while doing so.

One other thing to remember when looking at tosai, whether they are tategoi or not, is pay very little attention to body shape as this, like the gender of the koi, is unpredictable at this stage of their development.

I was not prepared to bet £600 on a 50/50 gamble and decided not to buy.



The system of grading tategoi in Japan is quite simple. After spawning normally in June, technically everything is tategoi because at this minuscule size there is very little to go on. As the months of summer pass the culling brings the numbers down and eventually the breeder is left with a number of pretty young tosai. At this stage he then pre-selects his tategoi, this is normally done at harvest time (October/November). These koi are the ones that the breeder deems good enough to grow to nisai (two years) and are now expensive to buy and will be further grown and reared throughout the winter months until May/June.


Just prior to going into the mud ponds in late spring/early summer these tategoi are now graded for the last time, and sometimes as little as 50% are put out into the mud ponds to grow on. The leftovers are now called ‘tateshita’ meaning second best or not quite making the grade.

Second Best Bargains

The number one ‘tateshita’ is still a very high quality koi, but the breeder cannot grow on everything and must draw the line somewhere. ‘Tateshita’ tosai are some of the best bargains to be had, as they are almost tategoi, but no longer carry the tategoi price tag. These koi can be very easily purchased as the breeder no longer wants them and sometimes accepts silly offers to get them out of the way. Their attentions at this time of year are turning towards spawning and normally they need to use all the space available.

When I am buying tategoi tosai in Japan I normally buy from breeders that I have a good relationship with, as over the years I have watched their koi grow and I can use this knowledge when selecting from them. Also they are far more accommodating with regards to the amount of money I want to spend on small koi.

Buying Tategoi

Many breeders are reluctant to sell their future fish at sensible prices, I was once quoted by a Japanese breeder over £600 for a six-inch Sanke, it was absolutely beautiful and I was extremely tempted to buy. The koi was not worth £600 at the time and would only reach this value if it a fulfilled a large part of its potential, i.e, turned out to be female and with good body shape, may be within one or two years.

I was not prepared to bet £600 on a 50/50 gamble and decided not to buy. Eight months later I returned to Japan at harvest time and the Sanke was 18in long and still looking beautiful, but very much a male fish that now had a value of just £80! This is why I never spend too much money on tategoi tosai.

Buying Tategoi Nisai

koiWhen I am buying tategoi nisai I am prepared to pay much larger sums of money as it is now a completely different proposition. The koi in order to qualify for tategoi status are definitely female, the shape is becoming much more predictable, and the brightness of skin and the quality of colour are now eminently more apparent. The koi has now fulfilled one year of their potential. To buy a two-year-old koi that is regarded as a tategoi by the breeder, you will always have to pay a high price.

If you are using the term tategoi in a purely translated form, it is just a word for a koi that might improve.

Value for Money

As with tosai, if you can find a koi carp for sale that was one away from making the tategoi cut, you still have a high quality koi that’s extremely good value for money. On the flip side, all the tategoi tosai that have turned out to be male or have poor body shape or just poor koi full stop, are now worth a fraction of their previous value.

Progressing Nisai

When the two-year-old koi are put out to grow to sansai (three years), the numbers have dwindled yet further but the quality stakes have reached another level. Not only in the way they look but also in the amount of money it would cost to prise these fish away from the breeder.

A koi can be regarded as tategoi long past three years, the Japanese still regard some koi as tategoi at seven years, quite simply because they still feel this koi has potential left, to either grow or develop further, or both.

The Meaning of ‘Tategoi’

Most people have seen the word ‘tategoi’ used quite liberally, it all depends on whose tategoi it is – a breeders, dealers and hobbyists tategoi are not necessarily the same thing. If you are using the term tategoi in a purely translated form, it is just a word for a koi that might improve. For me I only regard the breeder’s tategoi as the genuine article and these are the type of koi I often buy, but only from nisai upwards.

As with most aspects of koi keeping, knowledge is the one thing that gives you a big advantage when selecting koi (tategoi or anything else for that matter). So if you are new to the hobby or just wish to learn more, find someone who has the necessary knowledge and use it, as they are normally all too happy to share it.