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Koi Fish Behavior- Is It Different?

Like with any pet, sometimes your koi fish behavior will change. It can be worrying when your pond fish start acting differently, especially when you don’t know why. Spotting the reason for the change in your pond fish behavior can be more difficult than with other animals because fish are smaller and in water. You may have to get up close and personal with your fish.

These are some ways to protect pond fish >>

Koi Fish Breeding

Let’s put it this way: you’ll know if their breeding or not. Normally, they’ll swim lazily about, not disturbing each other or the water. Suddenly, the fish are ganging up on each other, pushing, jumping, flailing, and being more active than ever.

It also may smell a little weird… Looks like it’s spawning season! It normally happens around May or June, but it can differ depending on the area. If this isn’t the pond fish behavior you’re experiencing, keep reading for other reasons.

Koi fish behavior when breeding- all on top of each other

Pond Fish Diseases

Your pond fish behavior may change because they are sick. There are ways you can identify some illnesses easily but others may need a closer inspection of the fish and even the pond.

For example, if the fish need more oxygen because the water doesn’t have enough aeration, they’ll jump out of the water more. Parasites can cause them to scratch on objects, gasp for air, and clamp their fins. There are treatments available for these and other diseases or conditions, so don’t worry!

You can learn more about pond fish sicknesses >>

Koi fish with mouths wide open as if gasping for air

Koi Fish Hiding

Koi fish behavior doesn’t include fun games of hide-and-seek. If your pond fish are hiding then something is wrong, usually having to do with predators. Since fish don’t know any martial arts, they tend to hide instead. These are other reasons your fish will hide:

  • Predators
  • Change in water quality
  • New fish
  • They’re sick
  • It’s a new pond

You can learn more on why your fish are hiding >>

Normalize Your Pond Fish Behavior

Make like Back to the Future and return your pond fish behavior back to the way it was! Of course, maybe you’re thinking about taking out the fish, a component of an ecosystem pond, so you can lower the maintenance your pond needs. You could even turn your pond into a pondless water feature! Check out the process in this video:

Pond or pondless- you can decide which is better >>