8 Things We Bet You Didn't Know About Koi

Koi fish
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Koi usually like company and can be kept with other koi and goldfish.

Koi are not what you might consider a traditional pet, but they offer some of the same advantages. Koi can be a calming addition to an outdoor garden or an indoor pool or aquarium. Koi may look like large goldfish, but the two are only distant cousins. Koi are actually more closely related to the common carp. Here are several more interesting tidbits about these fish.

1. Koi were developed in Japan more than 200 years ago.

Nishikigoi is the Japanese name for koi, which means fancy or embroidered carp. There are more than 100 known varieties of koi, each of which has a Japanese name. Fish that are mostly white with specks of red are called Kohaku. White koi with some red and black on them are known as Sanke, whereas those that are black with some red and white are called Showa.

2. Koi can grow up to 2 to 3 feet or longer.

Pool size, food, the number of fish sharing the space, the age of the fish and water quality can all affect a koi’s growth. Before setting up a koi pond, you should consult a seasoned koi pond builder to ensure you are setting the environment up correctly.

3. Koi are omnivorous.

They can be fed commercial koi food, but they also eat shrimp, worms, insects, water plants, fruit, vegetables and even certain kinds of cereals. Koi do not have a stomach but instead have a straight intestinal tract that will digest a meal within approximately 4 hours.

4. Koi love company.

They may be kept with other koi or goldfish, as they are usually very docile.

5. Koi may change color throughout their lives.

Many of these changes are caused by pigments in their food. Some koi may turn white as they age.

6. Koi can survive under a thin layer of ice.

However, they do need a small opening in the ice to get oxygen, and they cannot survive if the water gets too cold or if it freezes too far below the surface.

7. Your veterinarian can advise you on how to keep koi healthy.

Before buying koi, contact your veterinarian for suggestions about maintaining a clean, stress-free koi environment.

8. Most koi can live for at least 20 years.

On average, pet koi will live 20 to 30 years. Some koi, however, have lived for more than 200 years. To enjoy a long life, koi need to be kept in a healthy atmosphere that has good filtration and water quality and no sharp edges on which they can injure themselves. They also need good nutrition, appropriate chemical levels and temperature and little stress. Causes of stress include poor water quality, parasites, crowding and toxic chemicals.

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