What to Feed Koi Fish in Your Backyard Pond

Koi fish swimming in a backyard pond

With their beautiful colors and playful splashing, koi fish make popular additions to many backyard ponds in Charlotte, North Carolina. Fish can’t cuddle or play fetch, so feeding your koi helps you bond with these flashy pets. You can keep your fish happy and healthy by knowing what to feed koi fish and what they shouldn’t eat.

Koi Fish Feeding Habits: What You Need to Know

Since koi fish thrive in ponds with natural water, many koi owners keep their fish in an ecosystem pond. These ponds offer koi fish an environment similar to a natural water source, allowing them to feed themselves.

In the wild, koi eat many pests that otherwise gunk ponds up, including:

  • Algae
  • Insects
  • Insect larvae
  • Worms
  • Seeds
  • Crustaceans
  • Vegetation

Natural Eating Habits

Koi in the wild scrape through muddy pond floors to find food. Some wild koi get tired of dredging for food and head for the surface, picking off insects, tadpoles, and other critters. 

If you prefer to let your koi swim on the wild side, pick specialized foods that sink to the bottom of your pond. However, be warned that bottom-feeding koi kick up muck while they hunt, so you may not be able to see them eating. 

Other foods settle on the water’s surface. As they battle each other for a mouthful, your koi put on a show that gives you a chance to monitor their growth and health. Feeding time can quickly become a form of entertainment for the whole family.

Catering to your koi’s natural eating habits depends on more than providing their food at their preferred level. Keeping your koi in good health depends on many factors, including:


Regardless of your koi fish’s age, providing them with a nutrient-rich diet keeps them healthy and boosts their immune system. Young koi require more protein than their elders. You can know what to feed koi fish by keeping track of when you purchased them and knowing if they’re breeding.

Oxygen Levels

Koi fish rely on a well-oxygenated environment to aid their digestion. Waterfalls provide ample oxygen for your koi while providing a charming addition to your backyard pond. If you have a broken or malfunctioning filter, repair it before the next feeding time.

Seasons and Weather

Your koi have a specific metabolism that changes with the seasons. Their digestion systems function best with a water temperature between 50 and 85 degrees Fahrenheit. When the temperature dips below 40 degrees, you shouldn’t feed your koi at all since they hibernate when temperatures reach that low and only reappear when the weather warms up again.

Koi also have cravings depending on the season. For example, they’ll want more protein during the spring mating season. In the fall, koi fatten themselves up for hibernation with healthy helpings of carbohydrates. 

Choosing What to Feed Koi Fish

hand feeding koi fish

Purchasing koi food from the store is the most beneficial for your fish. The best type of food for koi includes one of these two ingredients:

  • Spirulina Algae
    • Improves digestion
    • Boosts the immune system
    • Helps with energy production
    • Improves scale coloration
  • Wheat Germ
    • Improves growth speed
    • Increases oxygen flow
    • Promotes balanced growth
    • Improves blood circulation

Besides these two superfoods, your koi need fish-based food built from the same things koi might eat in the wild. Check the ingredients list to ensure your koi food includes proteins, carbs, and other necessary nutrients. You can trust foods that contain these ingredients:

  • Fish meal
  • Squid meal
  • Shrimp meal
  • Blood meal
  • Soybean meal
  • Whitefish
  • Corn gluten

Other nutrients your koi need include calcium and vitamins A, C, D, E, and K.

Choosing the Right Type of Food

Store-bought foods that meet the optimal requirements for koi come in flake and pellet forms. Flakes float on the top of your pond’s water and make the easiest food for small koi fish, while pellets either float or sink and work best for all sizes of koi. Choose the most appropriate size for the size of your fish.

How to Feed Your Koi

Hand feeding koi fish

Koi fish have specific eating habits in the wild that can be difficult to copy in your pond. Follow these tips to keep your koi happy and healthy:


  • Feed your koi a maximum of three times per day.
  • Adjust the number of daily feeding times depending on the season.
  • Sprinkle food gently into the water for up to five minutes per feeding time.
  • Feed koi away from filters and skimmers to ensure the food doesn’t get sucked in.
  • Skim uneaten food from the top of the water.


  • Let your koi eat for longer than five minutes at a time.
  • Make sudden changes in koi food.
  • Feed your koi right before, during, or right after rainfall.
  • Give koi grain-heavy foods too often.

Signs of a healthy koi fish include bright colors, shiny scales, and a strong but not overweight body. Adjust feeding schedules or fish food if you notice your koi gaining or losing weight, swimming sluggishly, or taking longer than usual to respond to food in the water. 

Koi-Safe Treats

Every pet enjoys the occasional treat, including koi fish. When deciding what to feed koi fish for daily meal times, you can choose treats that supplement their regular diet.

Buy koi treats at the store that include these tasty additions:

  • Silkworm pupae
  • Bloodworms
  • Larvae
  • Duckweed
  • Shrimp
  • Hyacinths

Feeding your koi fresh or cooked foods can be fun. Buy them human foods like:

  • Vegetables
    • Garlic
    • Broccoli
    • Squash
    • Lettuce
  • Fruits
    • Grapes
    • Strawberries
    • Melon chunks
    • Orange slices
  • Other Foods
    • Hard-boiled eggs
    • Cooked, unsalted rice
    • Cooked, unsalted pasta
    • Oatmeal flakes

Cut fruits and vegetables into tiny pieces so your koi can easily digest them.

Enjoy Healthy Koi in Charlotte, North Carolina

Now that you know what to feed koi fish, you can keep your pets happy and healthy. Visit our contact us page to connect with your local pond experts at Charlotte Backyard Ponds if you have questions about providing your koi with the best care possible or want to learn more about our services.