Breeding Koi Fish

breeding koifish

Some varieties of koi fish are extremely rare, and new types of koi are constantly being created. Some specimens are so prized that they can sell for tens of thousands of dollars. Because of this, it can be tempting for the novice keeper to consider breeding koi to sell.

However, keeping koi fish and breeding them are two entirely separate entities, as breeding priced koi is no small task and is often left to the professionals.  Only one fish in a 100 000 will have the traits to become a thousand dollar fish.

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koi fish eggs
Koi fish eggs

Koi fish breed through a process known as swarming, which gets its name due to the sheer numbers involved.

In the wild, common carp breed in extremely large numbers because most of the youth will not survive into adulthood. These numbers stay in play with domesticated koi fish.

The female koi lays a large clutch of eggs and then one or more male koi will fertilize the eggs. This can result in dozens of offspring through just one mating.

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There is a wide degree of variety that occurs when koi fish mate. This is how so many different types of koi have been brought into existence. Unfortunately, this is both a blessing and a curse to breeders. While occasionally a koi may pop up with a rare or new design, the overwhelming majority will appear very basic and will not even qualify as true koi.

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Narrowing Down the Numbers

This is where the process becomes much more difficult for novice breeders. Domestic koi are protected from many of the dangers that would destroy the majority of offspring. Having access to clean water, plenty of food and protection from any predators gives koi a sheltered life in which their survival rate from birth rises tremendously.

koi fish breedingBut since most of these offspring do not even count as koi, the breeder must separate them from the others. It can take a very sharp and well trained eye to spot early on which fish will become prized for their colors and which will be little more than a domestic carp.

The majority of offspring produced in koi breeding tend to be destroyed, something that some novice breeders do not have the heart for. Unfortunately, keeping dozens upon dozens of an ever increasing supply of common domestic carp is not cost effective. No one wants to buy them and they will continue to take up more space throughout breeding attempts until space and food become impossible to maintain.

Setting them free can also be dangerous as domestic animals released into the wild can be hazardous for the environment.

With these factors being considered, it is best that novice koi keepers get more practice and save up finances before trying to undertake breeding. Aspiring breeders are encouraged to start off small to get a feel for breeding koi. Amateur breeders should also be advised that the time and money put into breeding koi is not a means to get rich quick. The process tends to eat up more funds than it produces and is only a viable career option when done by professionals with a large operation.