about the butterfly koi

If there is one subject that is guaranteed to divide koi enthusiasts it's the butterfly koi. Many koi connoisseurs despise this particular variety and don't believe that these fish are even true koi. That said, for every yin there's a yang and on the other hand some keepers love their butterfly koi specimens and believe that they can make a wonderful addition to any pond. So what's the debate about exactly?


In the 1980s a group of brown and grey koi with long fins were discovered in a series of ditches in Indonesia. News travelled fast and a company in New York expressed an interest in the fish, ultimately importing some specimens. The fish did not prove popular as expected because, well quite frankly they were rather ugly! But a group of committed breeders were curious as to what could be achieved with these unusual fish and invested in a dozen specimens.

The Blue Ridge Fish Hatchery started to breed the long-finned fish with some of their finest koi. They were pleased to find that the long fin gene was dominant and so the fish could be bred back to colour without losing the unique nature of their fins. It also became apparent that the butterfly koi were very robust and highly resistant to disease. The son of the original breeder, Wyatt LeFever, commented that the koi looked like butterflies and the name stuck.


Butterfly koi become increasingly impressive as they age because their fins keep growing over a long period of time. A fully grown specimen is quite a sight and looks like a dragon moving through the water. Their barbels grow to an incredible length too and form elaborate patterns. Althoughbutterfly koi tend to have a smaller body size than regular koi, they can reach up to 40 inches in length given the right circumstances.


As with any koi, the patterns of butterfly koi can dictate their value. A good pattern with bright colours is a plus and these fish can look particularly striking in solid colours. Solid black specimens are really eye-catching. Black butterflies tend to grow larger than fish featuring brighter colours as their genes are not as strained. The scaleless Doitsu butterfly koi has a wonderful, glistening, jet black appearance. Even poorly coloured butterfly carp can look spectacular with those long fins!

The Fins

Butterfly koi can exhibit beautiful colouration but it is their long fins thatset these fish apart. Their fins grow longer due to a genetic mutation. As the fins grow to a greater length than normal, the rays can start to become wavy. The most valuable specimens are those which exhibit straight rays to the extremities of their fins. The length of the fins means that these fish must be handled with great care as their fins and tails are easily broken.

Real Koi?

Butterfly koi are genuine koi but have often been shunned by koi keepers. Now their popularity is increasing and top breeders regularly struggle to meet the demand for their fish, enthusiasts have become used to the concept of these unusual koi and are starting to embrace them too.

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