Koi, or Nishikigoi, are quickly becoming popular in the United States. However, few know of thier origins.

The first Koi were produced by breeding Carp such as the Asian and German Carp. After years of selective breeding, various color mutations started showing up. The first color patterns were recorded as early as 1805. Today, there are literally thousands of color variations available. The most popular colors found are white, silver, yellow, orange, red, black, blue and green. Combined with the patterns available, the possibilities are almost endless. Each noticeable pattern and color have their own names, which are typically as unique as the color they are referring too. Favorite types vary by country and location.

Koi are raised for purchase in countries like Japan, Singapore, Israel, and in the warmer American states such as Nevada and California. Koi can be purchased at most local pet stores. If they do not have stock on hand, typically they can be ordered. Ordering Koi has its advantages and disadvantages. You have more options when ordering Koi, since you do not have to pick from the stock on hand, but the disadvantage lies in the fact that you will not be able to pick specific Koi.

Koi, unlike most other fish, will continue to grow until they reach their breeds dictated size, no matter the environment that they are in. Baby Koi can be found as small as 3 inches. Jumbo Koi have even been know to reach lengths of three feet or more. The most common size found is around two feet in length.

Koi are omnivorous fish, which means they will eat both meat and plants. This means that their diets are very versatile. Koi will eat pretty much anything that you put in the pond with them, no matter if it is good for them or not. Since Koi do not have a sense of what is bad and good for them, as their owner you must control their diet. Another potential problem is over feeding treats. Again, Koi do not have the knowledge to know when to stop eating, and weight issues may come from overfeeding none nutritional foods. The healthiest treats for Koi are what they would find naturally in their ponds, such as earthworms and tadpoles, but it will not hurt to feed Koi treats such as Lettuce, bread, fruit, and veggies. You should pay special attention to the certain foods such as corn, beans, and grapes, as they contain an outer casing, which cannot be properly digested if swallowed by Koi. If you must feed this type of foods to your Koi, be sure to completely remove the outer casings before giving it to your Koi.

Koi are none-aggressive fish. This means that they are suitable to live with other fish such as goldfish or comets. The only issue you may find is smaller, less able fish may suffer from lack of food, as Koi are quick eaters. Koi are so mellow that they have even been known to be trained to eat out of their owners hand. Koi do not have teeth, so you will not get bit if you decide to attempt to feed your Koi out of your hand.

Koi have been known to live up to 30 years under the right conditions, so if you are thinking about buying Koi, you must consider this. The record for the oldest Koi is held by a Japanese Koi, who was 233 years old when he died.