A Guide to Feeding Koi

Feeding koi is very enjoyable, and many koi owners consider feeding the most enjoyable aspect of owning koi fish. As soon as you walk towards the pond, the koi will gather around you in hopes of getting a treat. Many find feeding koi fish a relaxing activity.

While feeding koi can be entertaining, keep in mind that feeding is also a very important aspect of koi fishkeeping for both hobbyist and professional breeders. The type of koi food that is fed and how it is fed can have a significant impact on the well-being of your koi.

What to Feed Koi Fish

While feeding the best koi food with the most nutrient rich content is important, as a koi feeding guide, this article will focus more on how to feed and best feeding practices. If you want to learn more about what to feed your koi and the types of koi food on the market, check out The Ultimate Guide to the Best Koi Food.

How Often to Feed Koi Fish

How often the koi is fed and the quantity that is fed is very important to the health of your koi fish.

In regards to the frequency of feeding koi, it is recommended to feed koi 2-4 times a day, what they can consume within 5 minutes.

This feeding frequency can be adjusted based on factors such as the age of the koi fish and the water temperature. For fry and juvenile koi fish, they should be fed more frequently in smaller quantities. Mature and older koi fish may be fed less frequently in comparison.

In regards to the water temperature, the warmer the weather more often the koi should be fed.

Feeding Koi Fish

When to Feed Koi

A good time to feed koi is one hour after sunrise to one hour before sunset. Since koi naturally forage for food all day, the feeding routine can be scheduled anytime during this period.

However, if the water temperature is cooler, be more selective when you feed your koi. Keep in mind that cold temperatures impair the koi’s ability to digest food. If the water temperature is below 68 degrees Fahrenheit, the feeding time should be scheduled only during the warmer parts of the day. A feeding routine that concentrates on feeding from 10:00 am to 2:00 pm is ideal.

How Much Should I Feed My Koi?

In regards to the amount of food to feed your koi, a general rule of thumb is to feed 2-4% of the koi’s bodyweight every day. This general guideline is applicable especially to younger fish that are growing rapidly. As the fish matures, they will requires less food. In addition, depending on the water temperature, the koi may require less food as well.

Another simple guideline to feeding koi is to feed when the fish are hungry. The fish will continue eating if they are hungry and lose interest in the food once they are full. To the untrained eye, all koi fish may appear hungry all of the time, regardless of how much food is given to them. However, as you continue to feed your koi on a regular basis, you will be able to tell if they are hungry or not by observing their behavior.

However, keep in mind that it is very possible to overfeed your koi. Until you are experienced enough to tell if you are feeding the right amount of food by observation, it may be a good idea to measure your feed amount. Many koi owners make the mistake of overfeeding their koi rather than underfeeding them. Overfeeding can have a negative impact on the fish in multiple ways. First, it can stress the koi’s digestive system and internal organs. Second, the food creates more waste in the form of fish feces or uneaten food. Both will degrade the water quality, which will ultimately have a negative impact on the koi’s health as well.

How often to Should I Feed Koi in an Aquarium?

In an aquarium, koi fish will need to be fed more consistently. Unlike koi fish living in a pond, they will most likely have less opportunity to forage for food such as invertebrates and other living organisms. In a pond setting, these live fish food can make up a significant portion of their diet. Since koi fish living in an aquarium will be more reliant on the food that is being fed, they will require more consistent and frequent feedings. If the water temperature is above 68 degrees Fahrenheit, feed your koi 2-4 times a day. If the water temperature is below 68 degrees Fahrenheit, feed your koi up to 2 times a day.

Another factor to consider when feeding koi in an aquarium is size. Since most aquariums are smaller than ponds, koi in an aquarium should be fed less. There are two main reasons for this. First, koi living in a smaller space such as an aquarium will have less space to swim. Therefore, they will require less food. The second reason why koi in an aquarium should be fed less is to reduce the growth rate. If you intend to keep your koi in an aquarium long-term, you may not want your koi to outgrow your tank so quickly. Of course, starving your koi fish is not a good idea, but koi fish can stay healthy with less food than what most people think. In fact, more koi die in captivity due to overfeeding rather than underfeeding. Feeding less food, especially high-protein food, is a good idea if you wish to reduce the growth rate.

How Long Can Koi Fish Go Without Food?

Koi fish can survive without feeding for prolonged periods, especially when they are able to forage for food in the pond.

A healthy koi can survive for an entire week without feeding during the summer. Therefore, if you see that your koi is looking bloated, it probably wouldn’t hurt to skip a day of feeding.

During the winter season, a koi may survive the entire season without eating if the temperature is too low. In fact, if the temperature is below 41 degrees Fahrenheit or colder, it is recommended not to feed at all.

How to Feed Koi Fish

There are multiple ways of feeding koi fish, but the two main methods of feeding can be categorized into manual feeding and automatic feeding.

Feeding Koi Fish by Hand

When manually feeding koi fish, simply throw a small amount of food into the pond. Once it is consumed, throw more food into the pond. Each feeding session should last approximately 5 minutes. Feeding too much food, especially in one feeding session should be avoided since it can put a strain on the koi’s digestive system.

When feeding koi fish in a pond, it may be a good idea to use a koi feeding ring. Feeding koi can get messy and the floating pellets can drift away towards a corner or get sucked into the intake of the aquarium filter. By using a koi feeding ring, the koi will learn to come to the ring for food. This will reduce the amount of wasted food as well.

In the beginning, koi fish may hide under cover when you approach the pond. However, once they get accustomed to you, they will gather around you and the feeding ring when you approach them.

Once the koi are really comfortable with you, they can be hand fed as well. This can be an enjoyable experience as you can see the koi grab the food from you directly and up close. If you have a particular koi that you want to feed a different type of food, such as medicated fish food, you can take advantage of the hand feeding method. Some koi owners regularly hand feed or spoon feed their koi when they need to feed a specific type of food to a koi, but not all of the koi in the pond. Feeding koi fish from a bottle can be an efficient way of feeding a target fish as well. Simply fill a baby bottle with koi food, and cut the end of the bottle nipple to allow the dry pellet food to fall through.

Feeding Koi with an Automatic Pond Feeder

Another way of feeding koi fish is by using an automatic pond fish feeder. Automated feeders are very useful because it allows you to schedule multiple feedings throughout the day on a consistent basis. If you have a busy schedule that does not allow you to feed your koi multiple times a day, or you like to go on a vacation once in a while, this may be the solution for you.

There are many different types of automatic pond feeders on the market today. However, the ability to set the feeding amount, frequency, and feeding schedule, are standard features on most of them. Some require a power cord, but others are battery operated. Battery operated models can be installed far away from a power source, but they do require regular battery replacements. While usually priced higher, some automatic pond feeders have solar panels for independent power generation. Lastly, be sure to purchase a model that allows the moisture to escape from the feed chamber. If moisture accumulates inside the feed chamber, the feed can spoil quickly. It can also cause the dry pellet to clump up and prevent it from dispensing.

Feeding Koi in the Winter and Throughout the Seasons

Feeding routine for koi must be adjusted throughout the season, especially during the coldest months in the winter. This is because koi, just like all other fish, are ectotherms. This means that these animals do not produce heat to maintain a constant body temperature. Their body temperature varies directly with the water temperature (ESI). For koi, this also means that when their body temperature drops, their digestive ability slows down as well. Therefore, feeding routine should be adjusted accordingly.

For a quick summary of how to feed your koi throughout the seasons, refer to the koi feeding temperature chart at the end of this section.

Feeding Koi in Winter

During the coldest months of the winter season, koi should be fed very little to none.

If the water temperature is below 41 degrees Fahrenheit, do not feed at all. When the water temperature is this low, koi will not be able to digest their food properly. Their activity level will be lower as well, and they will rely on their body reserves to survive.

Feeding Koi in Spring

When the water temperature starts to rise in the spring, food can be introduced to them slowly.

If the water temperature is in the range of 41-59 degrees Fahrenheit, you can start to feed your koi again. Start by feeding wheat germs sparingly, during the warmer parts of the day. Hours between 10:00 am and 2:00 pm would be ideal. Feed once or twice a day, as much as they can consume in 5 minutes or less.

Feed with caution and feed sparingly, especially at the lower temperatures of this range. At this temperature range, koi food that are high in protein and fat should be avoided.

Feeding Koi in Summer

During the summertime, the temperature rise and the activity level of your koi will increase as well. They will develop an appetite, and their digestive capabilities will return.

At temperature range in between 59-68 degrees Fahrenheit, you can start to introduce regular koi food that are higher in protein and fat content.  However, it is still a good idea to feed them during the warmer parts of the day. At the very least, avoid feeding one hour after sunrise and one hour before sunset.

At temperature range in between 68-86 degrees Fahrenheit, your koi fish will be able to consume the most amount of food. You can feed 2-4 times a day, what they can consume within 5 minutes. They will be able to consume food that are higher in protein and fat content. Color enhancing food can be fed at this temperature range as well. Their activity level will be higher at this temperature range, so their appetite should develop as well.

To summarize, here is a koi feeding temperature chart. This chart describes the optimal temperature range for various feeding frequency and feed types.

Koi Feeding Temperature Chart
Water Temperature (° F)Below 41° F41-59° F59-68° F68-86° F
Frequency0 times a day1-2 times a day1-2 times a day2-4 times a day
Wheat Germ Based FoodNoYesYesYes
Protein Based FoodNoNoYesYes

Koi Feeding Tips

  • Summer is a good time to feed high growth food to your koi. For the younger fish that are growing, the protein content is very important. For fry and juvenile fish, the fish food should have a protein content of approximately 50%. For fish that are in their adult stage, their protein requirements decreases. Approximately 40% protein is sufficient. Lastly, for mature fish that are not growing as much as the younger fish, their protein requirements decreases even further. The protein content can be as low as 30%.
  • Be sure to feed enough food for the fish, but make sure your filtration system is able to keep up. In an enclosed system, such as a man-made pond, it is important to consider the capacity of the filtration system. If the water is getting murky, it may be wise to reduce the feed amount. If you continue feeding the fish the same amount of food when the filtration system is not keeping up, it may further degrade the water quality. This will do more harm than good for the fish. The capabilities of your filtration system can be challenged especially during the summer. This is when your koi consume the most amount of food and are producing the most waste. This is also a time when the oxygen levels can get lower simply because the water is warmer.
  • Learn as much as you can about koi fish and the types of best koi food that are available. In nature, fish are able to forage for food whenever they want. As opportunistic feeders, they will feed on what they please throughout the day. In an enclosed system such as a pond or aquarium, it is the responsibility of the fishkeeper to identify the needs of the fish. If you take good care of your koi fish, it may live much longer than a carp in the wild could. In fact, some koi live a very long time.