The Koi (or “Nishikigoi” in Japan) are rapidly becoming popular in the United States for breeding. But only few people really know how and where they came to be. The first Koi were produced by breeding the German carp and the Asian carp. After years of careful selective breeding, different color mutations started showing up. In the year 1805, the earliest patterns in color were recorded. Up to this day, thousands of color variations and combinations can be seen.

Popular colors include yellow, red, white, green, silver, orange, black and blue. There are endless possibilities when it comes to color combinations. Each come with their own names, based on their pattern and color. There may be a difference in the favorite types, depending on the location and country.

These fish are being raised for sale in various countries, such as Singapore, Japan, Israel, and in warmer states in the U.S.. The fish can be bought at many local pet stores. If they don’t have the stock readily available, they can be ordered. By ordering, the advantage of this is that the buyer will have more options, due to the fact that they do not have to pick from the stock that’s on hand. On the other hand, the downside of this is that the buyer will not be able to pick the specific Koi they want to have.

Unlike most of the other fish out there, they will continually grow until they’ll reach the maximum size of their breed (no matter where they’re being placed in). The infant ones are in lengths of 3 inches, while the largest can reach up to 3 feet or even more! Their most common size reach up to two feet long. As for their age, they have been known to live up to 30 years old (under the right conditions), the oldest of which have lived up to 233 years!

The Koi are omnivorous, as they feed on meat and plants alike. This determines the versatility of the Koi’s diet. They’ll eat almost anything you give them, and it doesn’t matter if its good for them or not. The owner should be the ones to control what and how much they eat, as they have no ability to judge what’s good or not for their diet, and the amounts that they should take everyday. The best treats for them are those natural kinds of food, such as tadpoles and earthworms, and other treats like bread, lettuce, veggies and fruit.

Owners should take necessary precautions when feeding them with corns, grapes and beans, as these food contain an outer casing, which can't be properly digested by the fish if eaten by them. The outer casings should be removed completely before feeding those to them.

The Koi are non-aggressive types of fish, and they are able to mingle with other fish like the comet and goldfish. Quick eaters as they are, they have the tendency to eat smaller fish, and this could be a problem! The Koi do not have teeth, that’s why they can be fed through their owner’s hand (which can be a great past time for their owners too)!). For this, breeding is truly a fun hobby for fish lovers out there!