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Koi Varieties - Mukashi Ogon

Our latest blog post is the next in our group of posts all about Ogon koi. As we have discussed before, Ogon koi are a subvariety of koi that are all single-coloured koi with metallic skin. We have already looked at the Platinum Ogon, Orenji Ogon and Mizuho Ogon varieties and you can see all of our Ogon blog posts here:

Mukashi Ogon from breeder Aokiya

Today we are looking at the Mukashi Ogon (MOO-kash-EE oh-GOHN) variety which is the brown or bronze version of the Ogon. That is, the koi has a solid brown colouration over its whole body with a metallic sheen that gives the fish a bronze colour. Mukashi Ogon koi have often been described as a metallic Chagoi (a single-coloured brown koi) due to their similar colourations and are sometimes referred to as Penny Koi or Bronze Koi due to their unique colouration.

The Mukashi Ogon is one of the rarest varieties of Ogon koi due to a previous lack of interest or knowledge of the variety. In the 1980s and 1990s, Mukashi Ogon koi were not very popular and did not sell well to koi keepers. Many people assume this to be the case due to their uniqueness as they had not appeared in many shows and did not have the same reputation as the older, more established Ogon varieties. Over the late 1990s and early 2000s, the koi hobby took advantage of the internet and hobbyists began to use forums and social media to share their ponds and fish. Many varieties saw an increased interest around this time including the Mukashi Ogon presumably because most koi keepers were not aware of these varieties before. This led to a massively increased demand for Mukashi Ogon that the breeders were not able to keep up with. Since then, breeders have increased their breeding of this variety and, in some cases, started breeding them!

Doitsu Mukashi Ogon from breeder Aokiya

As mentioned above, Mukashi Ogon are very similar to Chagoi koi, only differing in the metallic sheen of their scales. This means that, like Chagoi koi, they are not bred very far away from the wild mirror carp that all koi carp were originally bred from. Therefore, Mukashi Ogon are also likely to grow to a larger size as their growth has not been stunted as much by the breeding process to produce the variety.

In fact, due to their similar colour to the wild mirror carp and the fact that it has a similar lustre to the metallic sheen seen on koi carp, breeders often introduce a mirror carp into the breeding process every few generations when breeding Mukashi Ogon koi. This helps to improve the metallic lustre and it also means that the variety is one of the healthiest koi varieties. Compared to most other koi varieties, the Mukashi Ogon is less likely to carry any genetic diseases or illnesses and the variety has much more natural resistance to parasites and other transferable health issues.

Pongoi (Best Quality) Mukashi Ogon Koi

Many koi keepers believe Ogon koi to be one of the easiest koi varieties to judge due to the simplicity of their pattern, or lack thereof. Certainly, when compared to the complexity of a Goshiki, for example, there are considerably fewer judging criteria as there is only one colour and no complex patterns or scale types. However, this simplicity does mean that the varieties are judged a lot more strictly. On the background of a single colour, any inconsistencies or imperfections are much more obvious and less likely to be forgiven. On a Goshiki, if all the other criteria are fantastic but there is a small imperfection, the fish is still likely to be judged well. On a Mukashi Ogon, there are not as many criteria to consider and there are many more individuals who are considered Pongoi that each one must be perfect to stand out.

Gin Rin Mukashi Ogon from breeder Marusaka

When we are judging Mukashi Ogon koi, we have to consider two criteria. Firstly, we need to consider the colour of the koi and its consistency. Many koi judges consider the consistency of the colour to be more important than the actual colour itself. In a Mukashi Ogon, the colour must be the same shade all over the head, down the body, through the fins and into the tail of the fish. Any deviation in the shade is considered to be an imperfection. Of course, the colour and shade of the fish is important too. For this variety, the ideal base colour is a paler brown as this gives the nicest bronze colour with the metallic sheen. A darker, muddy brown is also acceptable for this variety but it is less desirable than the paler brown.

The other criteria to consider for a Mukashi Ogon is the metallic sheen on the body of the fish. Just like the brown base colour, the most important thing about the sheen is that the amount must be consistent over the whole body of the koi and the lustre should have the same quality all over. A koi with poor but consistent lustre is considered better than a koi with both good and bad areas of lustre. The sheen should be visible over all areas of the body with no areas clearly lacking the reflective sheen. For a beautiful metallic koi, the skin should be shiny like a mirror and, on the brown base colour of the Mukashi Ogon, be comparable to a shiny bronze coin.

The Mukashi Ogon is a stunning but rarely seen fish. Having one of these koi in your pond will certainly make you the envy of many koi keepers as these beautiful fish are definitely hard to come by!

To browse our current stock of Mukashi Ogon koi, see our website here:

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