Should I Feed My Koi Fish? And More To Know

Should I feed my koi fish

As a koi pond enthusiast, you’ve likely encountered questions regarding the feeding habits of your fish. How often should I feed my koi fish? Are certain types of food better for their health or growth?

In this blog post, we’ll discuss some essential guidelines on when and how to feed your koi fish properly. By the end of this post, you’ll feel confident that you can take care of your koi’s diet.

Should I Feed My Koi Fish?

If you have an artificial pond with no natural food source, you must provide regular feedings for your fish. If you have an ecosystem pond, your fish can live off what their environment provides in terms of algae, insects, plant matter, etc. In this case, feeding koi fish can be more for fun and bonding than anything else.

How Often Should I Feed My Koi Fish?

The general rule of thumb is that you can feed koi fish 1 to 3 times per day, depending on how large and active your fish are. However, remember that overfeeding can be just as detrimental as underfeeding.

Another important factor to consider when feeding your koi fish is temperature. During colder months (50 degrees Fahrenheit and below), don’t feed them at all since their metabolism slows down significantly. Any uneaten food will just break down in the water and cause poor water quality or even algae blooms. They can get sick or even die if they eat when their body is hibernating.

As mentioned before, excess food breaking down in the water can lead to poor water quality, affecting your koi’s health and encouraging algae growth. To prevent this from happening, ensure that you consistently check the amount you feed them and adjust accordingly if necessary.

How Long Can Koi Go Without Eating?

Koi fish with mouth open

Koi fish can go for two weeks without being fed during summer. This is because they will eat small bugs, algae, and other things they find in the water for nutrition. However, if your koi show starvation (lackluster color or unusual activity), you should be sure to feed them more frequently. 

Koi can go through the entire winter without eating and should not be fed if the water temperature is 50 degrees Fahrenheit or colder. During this time of year, their metabolic rate slows significantly, so they don’t require as much food as at other times throughout the year. It’s best to wait until temperatures reach at least 55 degrees Fahrenheit before feeding them again. 

How Much Should I Feed My Koi Fish?

At a minimum, feed your koi fish as much as they can eat in 3 minutes once per day. At most, only give your fish only as much food as they can finish within 5-10 minutes 3 times per day. If there is still food left, reduce the amount you give them next time or split it up into more meals throughout the day. 

You’ll need to watch your fish and adjust the amount of food based on how much they eat and how much is left over.

Just remember, too much food can still lead to water quality issues, such as increased nitrates. This can cause algae blooms or oxygen depletion leading to fish illnesses, so keep an eye on things after feeding time.

What Do Koi Fish Eat Naturally?

Koi with fish food in pond

Koi fish are omnivorous, meaning they eat plant and animal matter. Koi fish can eat many kinds of food.

Algae: Algae is an important part of a koi’s diet because it contains vital nutrients that keep the fish healthy. This also helps to keep your pond cleaner and clearer!

Bugs: Bugs are another great source of nutrition for your koi fish and can be found in many areas in and around your pond. You can also purchase freeze-dried bug treats from pet stores, which can easily add this protein-rich food to your koi’s diet.

Plant Matter: Plant matter provides essential vitamins and minerals that help keep the fish healthy and active. Koi and goldfish can nibble on roots and leaves as snacks. Don’t worry; they shouldn’t eat enough to harm the plant.

Koi Food: Specialized koi fish food is available at most pet stores. This type of food usually contains all the necessary vitamins, minerals, proteins, fats, carbohydrates, and other nutrients essential for keeping these beautiful creatures happy and healthy. Make sure only to feed them high-quality koi food so they stay healthy.

Other: You can feed your koi fish wheat germ, brine shrimp, and blood worms.

What Human Foods Can Koi Fish Eat?

Several human foods can be safely eaten by koi. These include cooked peas, boiled potatoes, cooked squash, boiled spinach, cooked beans, boiled carrots, cooked sweet potatoes, cooked corn on the cob (without the husk), and cooked pasta (without any sauce or seasonings).

What Human Foods Can’t Koi Fish Eat?

No carbohydrates! This means no bread products as they are bad for their digestion.

Fruits like apples or grapes contain sugar that could lead to bacterial growth in your pond’s water. The same goes for many dairy products.

Greasy fried foods are also off-limits. They lack nutritional value for your fish can lead to clogged gills if consumed in large quantities.

Raw vegetables should be avoided because they are difficult for them to digest. They may also contain harmful bacteria or parasites that could make your fish sick.

Processed meats such as sausage or bacon should also be avoided as they contain too much fat for koi to consume safely.

Finally, processed junk food items like chips or candy contain too much salt or sugar (or both) and should never be fed to koi fish. 

Factors That Affect How Much And How Often You Should Feed Your Koi

Feeding many koi fish

Koi Size

Smaller koi need smaller portions; larger ones need bigger portions. Overfeeding them can cause digestive issues, leading to health problems or even death. 


During the summer months, when the weather is warm, and the water oxygen levels are higher, you can safely feed them twice a day—once in the morning and once in the evening—with slightly larger portions than usual. In winter, when water temperatures drop, you should only feed them cold-weather fish food. Once temperatures drop below 50 degrees Fahrenheit, don’t feed them.


As temperatures increase, so do koi fish metabolic rates, which means they need more food than usual to stay healthy and active. Conversely, when temperatures drop too low for activity levels, reducing their food intake helps prevent unnecessary weight gain while still providing enough nutrition to meet their needs. 

Water Oxygen Levels & Quality

With too little oxygen in the water due to overcrowding or excessive algae growth, the metabolism of your fish slows down significantly. This means they need fewer meals with smaller portions. Suppose you see signs of water contamination, such as murky water or odors coming from your pond. In that case, it’s best not to feed your fish until these issues are resolved since contaminated water can cause serious illness.

It takes a decent amount of effort to properly care for your koi fish.

Facts About Koi Digestion

Koi fish getting ready to eat floating food pellets

Koi Have No Stomachs 

A common misconception about koi is that they have stomachs, like humans or other animals, but this isn’t the case. Instead, food passes through their digestive tract without being stored or broken down. This means that it’s important you feed your koi only what they can eat in a single meal, as undigested food can cause problems in the long run if left uneaten. 

Koi Metabolisms Are Linked To Temperature 

Another lesser-known fact about koi digestion is that their metabolisms are linked directly to water temperature. As the water temperature rises, so does their metabolic rate—which means they eat more and digest food faster. On the flip side, when the water temperature drops (such as during winter months), their metabolisms slow down, and they need less food to survive.

Should I Use An Auto Feeder For My Koi?

Pros Of Using An Auto Feeder 

The primary benefit of using an auto feeder is convenience. With an automated feeder, your koi can still get their daily meals even if you’re away or forgetful. Automatic feeders make it easier to track how much food your fish eat, which can help you keep tabs on their health and nutrition. 

Auto feeders can be programmed to dispense specific amounts of food at different times throughout the day. This allows for better portion control than manual feeding. It helps ensure that every fish in the pond gets enough food without overfeeding them, causing uneaten food to lower water quality or increase fish waste. 

Cons Of Using An Auto Feeder 

The main downside of using an automatic feeder is cost. Automated feeders are more expensive than manual feeding methods. Some automated systems require batteries or electricity to operate, plus they require maintenance. 

Keep Your Pond Clean And Clear With Charlotte Backyard Ponds

Keeping a pond clean and clear can seem daunting, but with Charlotte Backyard Ponds, your pond can stay clean and clear for your koi fish.

We understand how important it is to keep your pond clean and well-maintained and are here to help you do just that. Fill out our contact form today to start cleaning up your pond with Charlotte Backyard Ponds!