Why Are My Koi Jumping Out of the Water?

an orange and white koi starting to jump out of the water

Why Are My Koi Jumping Out of the Water?

Koi fish do not jump out of the water very often, so if you notice your koi doing that on a regular basis, there may be underlying issues to resolve. At Aquatic Gardens, our pond service technicians can ensure a healthy aquatic environment for your koi. Continue reading to learn more about why koi jump out of the water and what you can do to get to the root of the problem.

Water Quality Issues:

Poor water quality is a leading cause of koi leaping out of the water. Koi can feel distressed if their pond has high ammonia or nitrate levels, pH imbalances, and excessive algae growth. Regular water tests and maintenance are crucial to ensuring optimal living conditions for your fish.

Lack of Oxygen:

Insufficient oxygen levels in the water can also drive koi to jump. This behavior often occurs in ponds with inadequate aeration or filtration systems. Ensuring proper oxygenation through aerators or waterfalls can mitigate this risk and promote a healthier koi pond ecosystem.


Overpopulation in your pond can lead to heightened stress levels among your koi, prompting erratic behavior like jumping. Ask a professional pond service provider to assess the density of your pond so your fish can have adequate space and prevent overcrowding.

Stress Factors:

Various stressors, such as loud noises, sudden movements, or predatory threats, can also cause koi to jump out of the water as a survival instinct. Minimizing these disturbances and providing sheltered areas within your pond can help alleviate their stress and jumping behaviors.

Inadequate Pond Design:

Poorly designed ponds with steep edges or lack of shallow areas can also increase the likelihood of koi jumping out of a pond. Creating gradual sloping edges and incorporating shallow zones within your pond allows koi to explore their surroundings without the risk of injury.

Behavioral Reasons:

Koi may exhibit jumping behavior as a natural response to their environment, such as attempting to catch insects or mating rituals. While occasional jumping is normal, frequent or excessive leaps may signal underlying issues that need to be addressed.

Parasitic Infections:

Parasitic infestations, such as anchor worms or flukes, can irritate koi, prompting them to jump to try and dislodge parasites. Observe your koi and proactively treat parasitic infections to maintain the health of your fish.

Temperature Fluctuations:

Extreme fluctuations in water temperature, especially when it gets too hot, can also stress koi and trigger jumping behavior. Installing shade structures or adding various aquatic plants helps to regulate the water temperature and provide refuge for your fish.

What to Do:

If you notice your koi jumping out of the water more often than not, take immediate action and test the water quality, assess the pond design, and look at the health of your fish. Do your part to create a thriving aquatic habitat for your koi, and find a local koi pond service provider for further assistance.

As the premier professional pond service provider in Southern California, Aquatic Gardens is here to resolve any issues affecting your pond and the health of your koi. We’re committed to helping you establish and maintain a healthy koi pond. Ask about our pond services today!