When To Stop Feeding Koi In The Winter

Koi Diet

A koi fishs diet should consist of protein, vitamins, minerals, and fiber. Their diet helps to keep them looking vibrant and healthy. There are many Koi prepared foods that give them all the nutrients they need in preparation for the fall and winter seasons. Healthy food particles that fall into the pond also keeps the pond environment healthy and safe year-round. So this poses the question of when to stop feeding Koi in the Winter.

When should you stop feeding koi in the Winter? You should stop feeding koi altogether once the water temperature reaches 41° F because their metabolism is very slow at this time. Koi will be in topor mode- a form of hibernation- at the bottom of the pond at this time. 

Koi mit Zierfischfutter | When To Stop Feeding Koi In The Winter-Koi Eating

Another thing that you will find out about Koi is that they love begging. When the weather is warm and comfortable, their appetite is quite good. Many Koi species will eat out of your hand. They also will follow you around the pond around feeding time. They seem to stick their little faces out of the water and seem to want to jump out of the pond when it is time to eat.

Koi History

Koi fish species are revered globally. They represent a feng shui harmonizing energy force. Not only are they beautiful to view, they are also very hardy. Beginning as a Japanese food source, Koi ponds are now a leading hobby that is for individuals and Koi breeders everywhere.. Their normal lifespan is 25 to 30 years; however, they have been known to live to age 100.

There are more than 100 different types of koi (nishikigoi). Koi are a member of the carp family. Their classification is based on their breeding varieties. They are identified by their patterns, coloring, and body type. The Koi species are omnivores creatures. This means that they eat other fish, spawn and eggs. Koi also eat algae and different types of fruit. Yes, they are known to also eat insects and bugs.

When To Feed Koi In the Winter

During warm water temperatures, you can feed them fish food twice a day or as much as they can eat within a couple of minutes. They are more active in warm water temperatures because they are cold-blooded (poikilothermic) vertebrates. Koi are pretty intelligent aquatic hominids. When water temperatures turn colder, the less they will eat. You must monitor their feeding so that food debris does not settle over the pond. This is bad because rotting food releases harmful gases that can become trapped in the winter water environment.

When To Stop Feeding Koi In The Winter - L.A. Ring, Road in the Village of Baldersbrønde (Winter Day), 1912, NG6658, National Gallery

If your outdoor Koi pond turns cold during the fall or winter, the Koi fish’s metabolism naturally starts to slow down. At this time, they spend a great a lot of time at the bottom of the pond. The cold dense temperature at the top of the water is generally 39.16 degrees F. Therefore, the warmest water is at the bottom which is why Koi spend more time at the bottom of the water in the fall and winter.

With proper feeding during warmer seasons that consists of high protein foods, the Koi can build up their fat storage cells for winter. When the water’s temperature starts to get cooler, i.e., 50 degrees F, then reduce how much you feed the Koi.

In other words, when their water is warm, they eat more and digest easily. When the water temperature is cold just the opposite occurs. So, you must monitor your outdoor water temperature because it vastly affects and changes Koi digestion rates.

When water temperatures range from 50 degrees F to 60 degrees F, feed Koi once or twice a day. But when the water temperature becomes colder, the Koi’s eating habits change. Their digestive system can take up to 4 days to dissolve the food.

You should only feed your Koi two to three times each week in the fall. Again, stop feeding them when the water temperature drops to 40 degrees F or a little below. The most important care in winterizing Koi is to prepare them for winter. You must start during the summer months. Make sure that your Koi are eating a healthy diet.

Torpor or Hibernation – Koi Sleep Without Eating In The Winter

When To Stop Feeding Koi In The Winter - Koi Sleep Without Eating In The Winter
Image by edmondlafoto from Pixabay

It is important to keep track of the water temperature during the fall and winter. When the water temperature falls below 41 degrees F, stop feeding them because they are ready to hibernate. Koi hibernation is called “torpor.” Torpor is a form of fish hibernation. Unlike animal hibernation e.g., bears, torpor lasts for a short period of time.

Koi hibernation is similar to having the body go through lowering its temperature, slowing down the heart rate, and the breathing rate is lessened. Aquarists state that when Koi enter torpor, that when they come out it in the Spring, it can take a little time.

Koi keepers have noted that as cold-blooded fish, they thrive well, especially with your help during the cold seasons. But, if there is a longer than usual winter season, this is not good for your Koi. Prolonged cold-water temperatures can harm their immune system.

Hibernating Koi means that not only does their metabolism slow to a crawl, but so does their whole immune system and body functions. Their body slows down, it does not stop. They nearly go motionless in order to conserve energy. You need not worry, this is normal.

In all practicality, when Koi hibernate during the colder seasons, you don’t want food lying in their digestive tract. Koi owners often make the mistake of feeding them too much even when the water temperature changes during the fall and winter. When Koi seem to beg, it does not mean that they are hungry.

Just like a koi’s heartbeat, a koi’s gut will continue to slowly process food and will also still house good bacteria essential to keeping the system in balance. The gut acts as an active bio-dome, encouraging beneficial bacteria and discouraging harmful bacteria that could potentially cause problems.

There is a myth that undigested food in your Koi’s body will begin to decay. Just like the whole body of Koi slowing down, so does their digestive tract. Their digestive system like a human encourages good bacteria while expelling harmful bacteria.

It is assumed that food remnants or food debris that has not been expelled by the Koi could lead to a bacterial infection that could kill them. Once you stop feeding them for the winter, do not feed them again until Spring where the water temperature warms to 55 and above.

Diet and Environment In The Winter

Remember that as hardy as the Koi species are, protect them and keep them safe. Check the outdoor water temperature often. Of course, there are other precautions you can take to keep Koi safe during the winter in ponds.

For example, look at your plant life in the pond which may need to be changed out also. Check your filters and pump system to ensure they are working well. If needed, use a de-icer or a specially designed heater.

What does hibernation mean for Koi? Watching their behavior at this time is most intriguing. You can see them nestle close to each other. Ironically, they line up together facing in the same direction. Do they nestle because they are cold? The answer has to be no, only because they are cold-blooded by nature.

Fish hobbyists believe their habit of lining up close to each other during hibernation is because they are sharing a warm pocket of water. With this manner of bottom water living, they can easily face in one direction together or they face opposite directions when they feel the warmth of water areas.

Although Koi are not being fed during fall and winter water temperatures, nature takes care of them. They are barely moving but they often scrape nutritious algae from pond growth to receive increased calories that provides energy.

Bringing Koi In From The Cold

In geographical locations with challenging winter seasons, many Koi owners feel better bringing them indoors for the colder seasons. Yes, your Koi can survive harsh winters naturally. It is understandable that bringing them indoors is more for you rather than the fish.

There are some pointers and tips that may help you once your Koi are indoors temporarily Whether you use an indoor pond, a large aquarium, or a tank, use some of the same water environment from your outdoor pond.

Please acclimate your Koi when transferring them to their new water domain. The new water and the old water must contain the same temperature and the same chemical makeup. This water terrain will cycle the healthy bacteria that they lived in from the outdoors.

Test the indoor water to ensure that ammonia or harsh nitrates are not present. Prior to bringing Koi indoors, set up the water environment so that there is no presence of poor water quality that could harm them. Also, no matter what structure you use to hold the Koi, first please put a covering over it.

Koi fish are excellent jumpers. Keep the covering on for a couple of days until they settle down. Keep the cover on, then remove the cover ever so slightly. If their jumping seems to have subsided, you can leave the cover off permanently.

Remember that the indoor Koi must also be maintained with quality filters, pumps, and fluorescent lighting. Koi grow quickly, nearly an inch a month. They can grow around 9 inches or more within the first year. Therefore, make sure that your indoor environment is spacious enough for these beautiful fish.

Koi depend on you to provide them food, the right environment, and predator protection. Feed them properly throughout the year is a great start. Koi is a hobby that allows them to be a pet like other pets that help to reduce stress and their movement and coloring gives you a calming effect.

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