Why Are My New Jersey Koi Fish Hanging Around My Waterfall?

If you notice your koi fish frequently gathering around the waterfall in your New Jersey pond, it’s not unusual! Waterfalls offer more than just aesthetic value for a pond—they also provide benefits that attract koi. Here are the primary reasons your koi fish may be hanging around the waterfall, and what it means for their health and well-being.

1. Seeking Higher Oxygen Levels

Koi fish are naturally drawn to areas with higher oxygen levels, and waterfalls introduce extra oxygen into the pond. As water cascades down, it mixes with air, releasing oxygen into the water below. This oxygen boost is especially important in warmer New Jersey months when higher temperatures reduce oxygen levels.

Tip: If you notice koi gathering around the waterfall more than usual, especially in the summer, consider adding an aerator to help distribute oxygen more evenly throughout the pond.

2. Temperature Regulation and Cooling Off

Waterfalls help regulate pond temperature by creating cool, oxygenated pockets. In New Jersey’s hot summer months, koi often gravitate to these areas to escape warmer water in other parts of the pond. By positioning themselves near the waterfall, they can access slightly cooler water and avoid overheating.

Tip: If your pond experiences high temperatures in summer, a waterfall can offer a comfortable retreat for koi. You may also consider adding additional shade or floating plants to reduce the pond’s overall temperature.

3. Enjoying Natural Water Flow and Movement

Koi are naturally curious and attracted to water movement. The flowing water of a waterfall mimics the natural environment and keeps them engaged, which can reduce stress and boredom. For koi, the waterfall can also stimulate their instincts to explore and move through varying water currents.

Tip: You can add small fountains or bubbler features in other parts of the pond to create multiple points of water movement, distributing koi activity and allowing them to explore different areas.

4. Avoiding Poor Water Quality in Other Areas

If your koi gather around the waterfall, it could be a sign of poor water quality elsewhere in the pond. Waterfalls help circulate the water, but if other areas lack movement, stagnant water may develop high ammonia or low oxygen levels. Koi sense these imbalances and move toward the waterfall for better water quality.

Tip: Regularly test your pond’s water parameters for ammonia, nitrite, and pH. If there’s a consistent issue, you may need to enhance filtration, circulation, or aeration to improve water quality across the entire pond.

5. Enjoying Added Cover and Safety

The area around a waterfall often creates natural shadows and places for koi to feel secure. Koi instinctively seek out areas of shade or cover, where they feel less exposed to potential predators or environmental stresses. Waterfalls provide a sense of shelter, especially when the surrounding pond area is open.

Tip: If you want to create more areas of cover, consider adding aquatic plants or rock structures to other parts of the pond. This way, your koi have multiple safe zones, helping them feel more secure throughout their environment.

6. Observing Potential Health Issues

In some cases, if your koi are unusually clustered around the waterfall, it may indicate that they’re feeling unwell. When fish aren’t getting enough oxygen, they may congregate around aerated areas like waterfalls to breathe more easily. If the behavior persists, it’s essential to check water quality and observe for signs of illness, such as:

Erratic Swimming: Koi that are stressed or unwell may swim erratically.
Visible Symptoms: Look for red streaks, spots, or bloating, as these may indicate infection.
Lethargy: Koi that hover near the waterfall without their usual activity level may be under stress.

Final Thoughts

Waterfalls offer a range of benefits to your New Jersey koi pond, from oxygenation to temperature regulation and movement. Seeing koi gathered around this area is often a good sign, but it’s important to ensure that the whole pond maintains a balanced environment. Understanding this behavior can help you provide the best habitat for your koi.

Have questions about koi behavior or pond health? Contact us for expert advice on improving water quality, enhancing pond features, and creating a safe, enjoyable space for your New Jersey koi fish!

Enjoy a healthy, beautiful pond year-round by scheduling a fall pond cleaning today! Our professional team will ensure your pond is debris-free and ready to weather the winter. Contact Atlantis Water Gardens to get started!

Read more information on winter pond care and tips, and videos on winter topics at these links:

Why Should New Jersey Homeowners Winterize Fountainscapes?

Can a Pond Freeze Solid in New Jersey? Essential Pond Depth Tips

Can You Keep Fish in a Pond Outside All Winter in New Jersey?

How to Prevent Ice Damage to Your Pond in New Jersey: Top Winter Survival Tips