Feeding Koi can be very enjoyable. They are easy to tame and will feed from your hand. Koi are omnivorous feeders, which is to say they will eat foods of both plant and animal origin. Anything you will eat you can assume a Koi will too.

Food is taken in through the mouth and is broken up by the pharyngeal teeth. The process of digestion begins as food passes through he fish’s digestive juices. The long intestines help to digest fibrous plant material and enable the fish to dispose of indigestible material through the vent.

If you want to make a friend of each Koi you own, then you must feed it personally and not just throw the food into the pond. Feeding is not only a metabolic process but it is also a social activity that creates bonds between the fish community itself and with us humans.

Koi are highly valued for their color and certain additives can be included in the diet to maintain and enhance the fish's natural coloration.

Carotene affects the red pigmentation, but if used at too high a concentration, even the white pigment on the Koi will turn pink. Spirulina platensis also enhances and fixes the red pigment, but does not turn the white to pink to the same extent. It is a type of algae found and cultured in Mexico and eaten by the people, since it contains a high level of protein. Initially, it was fed to Koi on account of its nutritional value and not because of its colour-enhancing characteristics.

Now that these have been established, it is fed to koi for only one month each year, usually during September, but can be given at any time, even during colder periods, at temperatures of 10c, but no lower. Some koi farmers feed it for the month before the fish go to market to bring out the best colours in the Koi. Good coloration is not only enhanced by good feeding, however. Healthy fish tend to have much brighter colors than diseased ones.

To bring out the color in Koi, particularly the white, you must provide good living conditions. Strong red and yellow pigments develop well in waters rich in green phytoplankton (single-celled plant). Because Koi are difficult to see in green water, it helps to feed a diet that will enhance the red pigmentation. Black pigment is enriched in hard water with a pH level of 7.5-8.5.

Remember, however, that changing the pH and hardness of the water can affect the toxicity of ammonia and nitrite. Color is created by pigments and these are produced from amino acids which are derived from the food. Certain foods contain natural coloring agents in greater amounts than others, so that if these former foods are fed then the Koi will develop better color. However, in excess, these foods will also produce an over abundance of pigment and this will spoil the colors.

Color feeding is known as iroage in Japan (bringing out color) and breeders have used it with great skill. Color feeding will not, however, put color where it does not already exist.

There is a wide variety of Koi foods available. They are commonly found in stick, pellet and flake forms, with the stick variety being the type of food normally preferred for an average pond.

Food sticks tend to float initially and then sink as they soak up water. Good quality sticks will not break up too quickly and will therefore allow fish feeding at all levels in the pond to obtain a regular source of food. A good, balanced food will contain all the ingredients required for fish to grow and remain healthy.

Hikari fish food is the worlds largest selling Koi foods. This brand is sold throughout the world. There are other Koi foods which may be equally as good. Follow the advice of your local dealer for feeding Koi. She or he will not steer you wrong, if she or he does they will lose a customer.