QUICK SUMMARY ↬ You can feed koi vegetables, fish food, fruit, and pretty much anything that doesn’t have a lot of carbs and sugar in it. You also need to feed them over a 5-minute period.
What do koi fish eat in the wild?
Koi fish are descendants of common carp. If released into the wild, koi that survive will eat meat and vegetables including the following:
- algae
- insects
- worms
- larvae
- seeds
- crustaceans
- vegetation
Even though they have been bred to take food from the surface, koi fish evolved to take advantage of a different strategy.
In the wild, koi scoot along the floor, sifting through the mud to find food. This tends to make muddy ponds messy.
Koi don’t have teeth. Instead, two fleshy barbels hanging from their mouth help them feel out the bottom of ponds.
Some koi have stopped cruising along the bottom and may instead try to hunt insects or other food or the surface.
What should you feed your koi fish
The majority of your koi’s diet should always be store-bought food optimized for their health. You have many options.
According to shape
Flake
Best for the smallest koi and for their fry (baby koi).
Pellet
Should be small enough for your koi to swallow whole.
Bar
Best for the largest koi, though small koi will nibble it.
Dispersal
Floating
The most fun to watch. Most koi will prefer to eat floating food.
Sinking
Some koi find this a natural way to eat, but it is hard to monitor.
Best ingredients for koi fish food
The nutritional value of the food is most important. The first ingredient should be fish-based and provides protein and most nutrients. The second is often carbohydrate which is also needed as well.
Primary ingredients that should be present in koi fish food are fish, squid, whitefish, shrimp, anchovy, blood, and herring.
Secondary ingredients that can be considered as well are wheat germ, soybean, and corn gluten.
Nutritional requirements for koi fish
You should also check over the label of your fish to make sure it meets your koi’s nutritional requirements. Here’s what you should look for:
- 32–36% protein content. Koi won’t benefit from any extra protein, but higher protein content isn’t bad.
- 3–9% fat content. Baby koi (or fry) needs more protein to grow, while the older fish needs less unless sick.
- Low in phosphorous. Excess phosphorous in your pond will reduce your water quality and promote algae.
- Koi fish also need small amounts of other nutrients like calcium, vitamins A, C, D, E, and K.
How to feed your koi fish
The biggest mistake new koi owners make is over-feeding their fish. Follow these instructions to keep your koi healthy and colorful.
Sprinkle food very slowly, for a maximum of 5 minutes
Koi should be eager to eat and not leave any food untouched
Feed your koi up to 3 times a day. Less during cold weather
Feed away the skimmer
Foods you can give your koi as treat
These are fun foods that koi often enjoy but usually not for koi. Feed them with these 2–3 times a week.
Vegetables
Garlic, broccoli, leek, endive, cauliflower, squash, and lettuce.
Fruits
Melon, grapes, kiwi, strawberries, mandarins, and oranges.
Other treats for koi
Hard-boiled egg, oatmeal flakes, cooked rice, cheerios, pasta, and whole wheat bread.
Note about koi treats from your kitchen
Vegetables are too hard for koi to nibble. Cut them into pieces at least as small as your koi’s pellets.
Grans are very fattening and should be fed the least. On the other hand, cheerios can help an underweight koi.
Fruits are soft enough for koi, so some people cut them into slices and let the koi bite them.
Pasta and rice need to be cooked and without salt. Otherwise, they will expand in the koi’s stomach.
Store-bought koi fish treats
Some of the treats that you can purchase from the pet supplier are nutritious and can be fed more often than bread or other homemade treats. Options include:
- silkworm pupae
- bloodworms
- tubifex worms
- earthworms
- black mosquito larvae
- wax moth larvae
- tadpoles
- shrimp
- clams
- duckweed
- hyacinths
Foods to avoid feeding to koi fish
Though koi are flexible fish, there are a select few foods you should avoid feeding. These include:
- fish you caught
- bugs
- peas
- corn
- white bread
- frogs
