Traits & behavior
Koi eat both plant and animal matter, including prepared, live, frozen or freeze-dried foods and certain vegetables.
With proper care, your koi could live to be 50 years old or more.
Koi are generally a peaceful species, but may pick on slower moving fish.
Over time, koi will come to recognize their owners and may be trained to take food directly from your hand.
Things to remember
Whether you're just starting your pond or introducing new fish, don't forget to add only 1-3 at a time.
Safety & cleanliness
Please remember that all pets may bite or scratch, and may transmit disease to humans. Keep your pet's home clean and wash your hands before and after handling your pet or cleaning his home. Infants, young children, pregnant women, people with compromised immune systems, and the infirm or elderly are at greater risk of infections and should use caution when in contact with the pet or its habitat. Consult your doctor for more information.
Koi are big eaters and not terribly choosy about their diet. They will accept most types of prepared koi food, as well as frozen or freeze-dried foods.
Be sure to include plenty of plant matter in your koi's diet. Wheat germ pellets, chopped fresh or frozen spinach or other vegetables and spirulina (a type of nutritious algae) flakes are great choices.
For optimum health, feed your koi as much food as they will consume in 1-3 minutes, twice a day. You can alternate between regular staple diet feedings and 2-4 meals per week of a specialty food. In cold climates, it's normal for koi in outdoor ponds to stop eating when the water temperature is consistently below 45° F.
Signs your koi are healthy:
- Eating vigorously and swimming at all levels of the tank
- Clear eyes, smooth, clean skin and fins free from any lesions or inconsistent colorations
- Calm, steady gill movements
Things to watch for:
- Lying on bottom of aquarium
- Poor growth or weight loss
- Inflamed gills, skin or fins
- Fins clamped to sides
- Scraping body on rocks
If you notice any of the signs described above, check your aquarium water quality and consult a PetSmart Aquatics Specialist.
Because of their large size and fast growth rate, koi should be kept in a large outdoor garden pond. A good guide is at least 50 gallons of water per koi.
Koi have strong mouths and like to dig, so be sure to protect the roots of pond plants with a layer of gravel.
Koi are generally peaceful, and will do well in a pond community with other koi and comet goldfish.
Test water weekly to assess water quality. It is recommended that 10% of your pond water be changed per week. At the very least, 25% of your pond water should be changed per month.
Koi require a cool water environment with an ideal water temperature ranging between 65-75° F. However, they can survive in temperatures above or below this range. In cold climates, koi will lay dormant in the water under the ice during the winter. Make sure the pond is at least three feet deep to prevent it from freezing solid.