Foods for Koi and Goldfish

Koi and goldfish originated from the Asian carp. Goldfish were developed for both color and body shape in China, while koi were bred in Japan for their colors and markings. Koi and goldfish are kept in outdoor ponds and forage through the substrate in search of edible matter. Koi tend to be less hardy than goldfish and require better water quality and diet. The standard diet of koi and goldfish should comprise a prepared dry food in pellet form.

  1. Use of Commercial Diets

    • Commercial diets are typically well balanced and easy to feed to either koi or goldfish. In warmer water with a temperature between 60 and 85 degrees Fahrenheit, you can offer koi and goldfish a good quality commercial food between two and four times daily. At these temperatures, the fish's metabolism is high and they require a high protein commercial diet. Once the water temperature falls into the 50 to 60 degrees Fahrenheit range, you should not offer these fish food more than twice daily. A commercial food with low protein content is best during cooler months.

    Nutritional Value

    • Goldfish and koi digest and use proteins derived from fish far better than proteins found in beef, chicken, lamb or pork flesh. The best commercial foods for goldfish and koi are made from fish meal and do not include mammal organs or meat. Fat is valuable in the diet of both goldfish and koi but can cause a commercial diet to spoil in very hot weather. A fat content of between 3 and 9 percent is most suitable. Although carbohydrates offer an energy source, koi and goldfish metabolize carbohydrates poorly.

    Live Foods

    • Live foods are highly nutritious and easily accepted by these fish. Supplement the standard dry food diet of koi and goldfish with live foods on a weekly basis. Earthworms are a valuable food. Remove excessive earth from large worms by pulling the creature through your fingers. Smaller koi and goldfish of most sizes readily accept blood worms and tubifex worms, but these worms should be thoroughly rinsed in running water before feeding them to the fish. Tiny fresh water shrimp are also an excellent dietary supplement for koi in particular.

    Vegetables and Fruit

    • Goldfish and koi eagerly accept fresh vegetables, such as romaine lettuce, peas and zucchini peas. Blanche these vegetables in boiling water or steam prior to feeding to assist with digestion. You can offer fruit such as bananas and grapes occasionally to koi in particular. Offer bananas as small pieces which the fish can easily swallow.