What Do Koi Fish Eat? The Ultimate Guide

Feeding koi fish is a beautiful and rewarding experience, seeing them glide up to you with their various colors ready to eat.

What do koi fish eat? Koi fish will eat anything that is put in front of them from specialty food, human food, to whatever comes along in their pond. But that doesn’t mean they should be fed just anything.

Due to their body makeup and being omnivores they need a special diet that will give them the nutrients that they need while also something that their bodies will process.

The food itself is not the only thing to worry about when feeding koi, you must also consider when they are eating and how they are being fed. And we can help you with that process.

Read further to learn exactly what your koi can eat, the feed process, and what kind of store-bought food is the best for them.

What to feed your koi

Koi fish are not picky eaters, they will eat anything and everything. They just like food. But to keep them healthy you as the owner have to be discerning when it comes to feeding your fish.

Just because they will eat anything doesn’t mean you should just feed them whatever sounds fun. Thankfully this openness to eating makes it easier to know what to feed them.

Koi are omnivores that feed on plants and algae just as much as they will chase a random insect that has the misfortune to come into their pond. Even though they are peaceful fish they still will take a bit out of smaller fish that are in their territory.

As a result, they need both protein and carbohydrates. In the wild, they eat the aforementioned plants along with crustaceans and worms.

For this varied diet, the best food will contain both protein and carbohydrates. Koi food can come in the form of flakes, pellets, sticks, and even powered form that you can mix.

This type of food should be the main form of substance and should be the only thing that they eat during the fall and spring months due to their lowered metabolism.

You will need a couple of different types of food, summer months are more protein-heavy while the cooler months your koi will need more carbs. Not only do these specialty foods provide the right vitamins and nutrients they also provide substances that will help keep their colors vibrant.

You must also learn what not to feed your koi.

• Beans
• Peas
• Potatoes
• Bread
• Rice
• Live fish that you have caught

The food that you buy your koi will have the correct amount of carbohydrates for them. However, a lot of people use human food as a treat for their koi. Avoid foods that have a lot of carbs such.

These foods take a long time to digest which is hard for your fish that lacks a stomach.

Your koi pond is a sterilized environment introducing a fish that you do not know could spread disease in your pond or bring parasites. If you want to feed them something live then go to your local pet store or dealer for feeder fish.

These are fish that are breed for the sole purpose of being feed to other fish. If you rather not see your koi go after something living they also come in frozen and dried forms.

Treats for your koi

Koi fish love treats and they especially love human food as a change from the pellets or flakes that you typically feed them.

Human food should only be used as a treat for your koi instead of their main source of food. Think about what you are feeding them before taking snack cakes out to the back yard.

Is the food that you are about to feed your koi healthy for you? If it isn’t then it isn’t healthy for your koi.

Avoid feeding your koi anything comes out of a cardboard box. Treats should be natural to get the best vitamins and nutrients possible. Think about the procedure that goes into creating processed foods.

A lot of foods that come in cardboard boxes have chemicals that don’t agree with your koi’s system. Carbs, salt, and high fructose corn syrup along with added chemicals that could affect your koi’s heath.

These types of chemicals don’t contribute to your fishes’ health nor provide any nutrients, they just taste good. When your koi eats these items it limits their ability to absorb needed from healthy proteins and carbs.

It’s best to stick to natural foods when giving your koi treats. They will enjoy it because it’s a change of pace, but these natural foods will also contribute nutrients.

Practice moderation when feeding your koi human food. This is a treat, not their main source of food.

Types of human food koi can eat:

Orange slices, grapes, and watermelon are fruits that your koi will enjoy eating. Look for soft fruits that are easy to break up. Oranges and grapes you can break up by hand and feed them.

For watermelons cut a thin slice and throw it in the water. They will circle the slice and nibble on it. After they are done scoop the slice out so it doesn’t foul the water.

Other fruits that work well for koi are soft melons, citrus, berries, tomatoes, and bananas.

Koi fish love broccoli, cauliflower, cabbage, lettuce, radishes, and leeks. Anything that isn’t too heavy on their digestive system and is light enough for them to suck into their mouths to chew since their teeth is at the back of their throat.

For denser veggies like radishes cut them in pieces small enough for your koi to handle. Starchier items can be feed to your koi, but use caution for legumes, rice, and corn since it takes longer for them to digest.

If you are worried about the texture boil the food then allow it to cool down before feeding your koi.

When it comes to meat stick with things that they could find in the water. Don’t bring them beef because their digestive system might not be able to handle it. Smaller animals such as snails, shrimp, or worms are the perfect meat product for them to eat.

Either frozen, dried or fresh doesn’t matter they will eat it. One thing that you shouldn’t do is bring back live fish that you have caught while fishing.

If you want to put fish in your koi pond for the specific reason for your koi to eat then go to your local pet store or fish dealer and ask for feeder fish. These are cheap fish that are breed specifically to feed to other carnivores of omnivore fish.

When you purchase for a reliable source you know that the fish, even if their only purpose is to be eaten, is not diseased or carry parasites that can spread to your koi.

Also, this might go without saying, but parasitic worms are not good to feed your koi. Things like maggots, ugh, live off of rotten meat if you feed your koi these nasties they will get bacteria from the meat the maggots have consumed.

I’m sure you won’t mind this exclusion.

Here are some of our articles that we also recommend reading in this regard:

How to feed your fish

For koi, you can just toss in some food once a day and expect them to thrive. They need periodic feeding throughout the day that increases in the summer and decrease in the spring and fall months.

They don’t have a stomach to process food, using their intestines to digest their food. Making the feeding process more complicated. Feeding them a lot at once is too much for their system and it will take longer for your koi to digest their food.

When feeding your koi a little bit at a time is the best way to go.

The number of times you feed your koi depends on the season, which is covered below. During these feeding times be cautious about how much you give them.

Feed your koi for up to 5 minutes each time making sure they are getting enough food. The amount of food depends on the size of your koi fish. Smaller fish will not need as much food, while a jumbo koi can put down a lot more food.

Keep an eye on the weather when you feed your koi. Don’t feed your koi before a storm. They need a lot of oxygen for digestion, during a storm, the oxygen in the water will drop down and they can’t go to the surface to breathe.

Without enough oxygen, they will begin to stress out. With stress, their immune system will be affected causing parasites and disease.

You can feed your koi by throwing the food in their pond allowing them to swim to get what they need or you can hand feed them the food. When you throw food in the pond you might overfeed them.

After they are done you will need to scoop out any uneaten food so that it doesn’t contaminate the water with decay. Hand-feeding is perfectly safe and easy if you don’t have a lot of fish in your pond.

Koi do have teeth, but they are far back in their throat so they don’t pose a danger to you when feeding. At the very most they might suction your finger mistaking it for food.

Hand-feeding allows you to feed them exactly the right amount of food. Also, the process creates a stronger bond between you and your fish. You will begin to recognize their particular behaviors and patterns when you have a more personal experience with them.

When you are away, either due to a busy schedule or going on vacation, try to find someone who can come over to feed your koi. If you can’t find someone that you feel is capable of feeding your fish invest in an auto feeder.

Indoor auto feeders are easy to find, but if you have an outdoor pond make sure the feeder is specifically for outdoors. These feeders can be times and have portion control capabilities.

Feeding schedule for feeding koi

The season also plays a part in the type of food that they need or if they need food at all. Koi fish are cold-blooded creatures so their need for food changes due to the temperature.

They also don’t have a stomach and rely on their intestines to process their food, when their water is cold they will go into hibernation. During the summer and spring months their metabolism is high and you can feed them more.

But during the winter it will slow down and they don’t need as much food or doing need food at all.

If you feed your koi treats only provide them once the water gets around 65° F. Once the water gets to this temperature your koi’s metabolism will start to kick back and you will be feeding them several times a day.

During the colder months, their metabolism will decrease then stop in winter. If you feed them treats during this time they will not get the need nutrients from their specialty food.

Koi hibernate during the winter months so they will get little to no food. It’s important to give them enough food during the summer and fall months so that they have enough nutrients to last through the colder months.

The temperature where you live plays a part in your koi’s feeding process. If you live in a warmer environment that has mild winters your koi will have less of a hibernation time and will be more hungry throughout the year.

In colder environments, they might have a long hibernation time so feeding during the summer and fall is important to get enough nutrients in them before the long sleeping process begins.

During the cooler months before and after winter feed them carb-rich foods such as wheat germ. In the fall this type of food is to prepare their system for hibernation, while after winter they need to adjust to eating regularly again.

During the hotter months protein-rich foods, and treats, are perfect because that is when their metabolism is the highest.

It’s hard to determine when you should feed koi with changing temperatures and the degree amount varies from person to person, but here is a handy guide to go by.

• Extreme heat 95-over 100° F – Koi will lose their appetite, feed once or twice a day
• 75-95° F – Four to five times a day
• 75-65° F – Four times a day
• 65-55° F – Three times a day (start to decrease their protein intake)
• 55-50° F – Two times a day
• 50-40° F-Start feeding them three times a week
• Under 40°- Stop feeding them

If the temperature is above 75 degrees Fahrenheit then feed them around 5 times a day. Due to the heat, their digestive system will process the extra food fast.

Once it gets below 75 degrees you can start skipping at least one meal to get them to the point where they are ready to hibernate. Under 65° and you can feed them 3 times a day and decrease their protein intake.

Once the temperature outside gets to about 50 or 55 degrees Fahrenheit their metabolism is going to drop considerably, if they are taking food then feed them twice a day. If they don’t partake in any food don’t worry they are just hibernating.

If they need something to eat during these periods’ algae, plants and any bugs that come into their pond will be more than enough. When you first get koi it might be easier for you to hand feed them.

This personal approach helps you to see when their appetites start to decrease and you will have a better gage in the future years to come.

Best store-bought food for your koi and auto feeder

Koi need specialty food so that they have enough nutrients throughout the year and to keep their colors bright. Since they are omnivores you can’t just go out and buy anything for them, and feeding them human food will ensure that they are missing some nutrients.

It is a very tricky process making sure your koi are feed right, both the amount of food given and frequency throughout the year.

While you still need to feed them yourself at times to create a closer bond between you, if you feed your koi they will come up to greet you when you walk out, it can be hard for you alone to keep up this process.

If you work at home or are at home throughout the day, then it won’t be a big deal. For those who work or might be gone for vacation or whatnot, it becomes a hassle to make sure you are caring for them properly.

Luckily there are auto feeders that will help you care for them when you are away. You can also set up the auto feeders to calculate the frequency so that it changes as the weather gets colder.

Store-bought food

During the warmer months, Tetra Pond Koi Vibrance (you can get it here) is a good general choice for your koi. It comes with the protein, fats, fiber, and vitamin C that your fish need.

This particular formula is best used when the water is above 50° F. Koi Vibrance is a stick form of food and will float on the water, making it easier for you to clean if there is any uneaten food left.

When the water temperature falls below 50° F you need to switch to the TetraPond Spring and Fall Diet (you can get it here). Like the Koi Vibrance, this is a stick variety of food. While this food does have protein, fats, and vitamin C it is high in fiber due to wheat germ.

When you are feeding your koi this type of colder weather food you will also limit the times that they eat per day.

Hikari Gold Pellets (you can get them here) are an all-around food source for your koi, but they are specifically made to help with the vibrancy of your fish. This brand is made in Japan so it might take a bit to arrive depending on what shipping method that you chose.

With fish food, it is ok to provide a mix to your koi so they can eat this and a more general type of food.

When you need to be away or are just busy an auto feeder helps keep your fish feed regularly if you have no one that can help. Not all auto feeders work outdoors, the mechanism and food are not protected from the rain.

Automatic feeder

The P7000 Pond Fish Feeder (see it here) has a timer and portion control. The cup capacity is at 30 so you can fill it up if you are going to be away for a little bit. The model only takes sticks and pellets.

Flakes are great when you are hand feeding your fish but are not substantial enough for a lot of auto feeders due to clogging.

A word of caution for store-bought food. While it might seem thrifty to buy bulk food for your koi it’s better to get smaller bags. A koi’s food needs change so often throughout the year, so any unused food that you have will stay in its container for a year.

If you buy in bulk you might have half of a container of food that will rot. After you own koi for a while it will get easier gaging the amount of food you need to buy during each season.

Just because your koi will eat anything doesn’t mean you should be feeding them just anything. You being the rational party need to be discerning in what you feed your fish.

Feeding them specialty food ensures that their nutritional needs are met. While feeding your koi novelty foods or human food is a cute error on the side of caution. They don’t have a stomach so digestion is harder for their system than it is for yours.

If it isn’t great for you then it is doubly bad for them. Feeding them correctly will guarantee they will be your friends for at least 20 years.