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Why Are My Koi Fish Hiding Or At The Pond Bottom?

Find Out What’s Bothering Your Fish In Your Maryland, DC, Or Northern Virginia Pond

You can learn some of the reasons your fish are hiding by reading this post. There could be predators nearby, they could be sick, or it could be something else this article covers. Your koi fish always hiding can be frustrating, especially since it’s one of the reasons people install a backyard pond. Thankfully, most of the situations causing your koi fish to hide are easy to deal with.

You can also read our Guide to Keeping Your Fish Safe, Happy, and Healthy >>

Why Are Your Koi Hiding?

Koi fish have several reasons for hiding. One of the main reasons is because it’s a self-defense mechanism. When people are scared, they either fight or run and hide. Fish aren’t known for their fighting skills, so they hide instead. By hiding, your koi fish are protecting themselves from some form of danger, including new ponds.

Koi fish hiding in aquatic plants

Have you recently added new fish?

After adding new koi fish to your ecosystem pond they’ll be a bit skittish. It’s like moving into a new home. You want to get all settled in before you go exploring and meeting neighbors, but unlike your neighbors, any fish you had may hide too! It may be a while before they all come back out, but you can try to use food and coax them out. If it’s not because of new fish, it could have something to do with the water.

Koi fish always hiding because of new fish

Have there been any changes in water quality?

Change is stressful, even for koi fish. Water quality, pH levels, or oxygen levels changing can be the cause of your koi fish always hiding. You’re going to need to test the water, which is as easy as making brownies- just follow the directions! There are test kits you can buy that’ll quickly give you a pH reading by adding a solution to a sample of the pond water. Test it in the morning and evening to get an average pH level.

You’ll want to use an aerator to oxygenate the water. This is especially true for the summer when water holds less dissolved oxygen. Without the right levels of dissolved oxygen, your fish can start having health problems. You can easily add artificial aeration if needed. Also, be sure to check your skimmer regularly because it may need cleaning or a replacing of the filter mats.

Diagram of winter and summer placement of pond aerators

Have there been any recent visits from predators?

Que the “Jaws” theme song. Herons, raccoons, and other predators like to hunt in ponds. This can cause your koi fish to hide more often out of fear of becoming fish food. One of the best ways to protect your fish is by installing fish tunnels or caves. You could also install a motion-activated sprinkler and put it near the pond. It’ll spray any predator bold enough to try fishing in your pond, including cats. Of course, this isn’t a permanent fix because, after a while, predators will realize it won’t harm them.

koi fish always hiding because of predators like this blue heron

They may be feeling sick

Stressed or sick fish will also hide. All animals hide when they feel sick. Don’t be alarmed. These sicknesses have medications and are treatable. You can also use salt treatments. Make sure to contact a fish professional before adding anything to your pond. The medication can be tricky and treating the water with salt can harm the plants.

No More Fish Hiding

Now your koi fish always hiding shouldn’t be a problem! You can get your fish out of their hiding spots and back into the open. You’ll once again be able to enjoy watching them swim around and feed them in peace. Except for in winter when the pond freezes over and then you’ll need to care for them in a different way.

What to do with pond fish during winter >>