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Why is My Cory Catfish Not Moving? (6 Common Reasons)

Why is My Cory Catfish Not Moving? (6 Common Reasons)

This post is written to the author's best knowledge and is not intended to be used in place of veterinary advice. In addtion, this post may contain affiliate links. As an Amazon Associate I earn from qualifying purchases.

You really enjoy keeping cory catfish in your aquarium. These fish are among the best fish to choose when you’re putting together a community fish tank, and they can be great to own in other scenarios as well.

If you go to check on your cory catfish one day and find that one of them isn’t moving, you’re going to be worried. Why would a cory catfish suddenly stop moving?

Of course, you’re likely concerned that the fish is dead. Is the fish simply being lethargic or has it perished?

Read on to learn about some reasons why a cory catfish will stop moving. You’ll learn about causes of sluggishness as well as how to determine if a fish is alive or not.

1 – The Cory Catfish Could Be Resting

Hopefully, the fish is just resting and you don’t have anything to worry about at all. Cory catfish are known to take short naps at random times.

They’re considered to be diurnal fish that are more active during the day. However, they don’t really have a normal day and night cycle.

Unlike most fish, cory catfish will just rest when they feel the need. They will lay down and take little five-minute long naps.

You might have just caught the cory catfish during one of its naps. These fish will rest like this both during the day and during the night.

Note that it’s standard for cory catfish to lay on their sides. That’s normal behavior for them.

2 – Is the Fish Injured?

Fish can get injured for various reasons. There’s a possibility that your fish might not be moving because it got hurt in the fish tank.

Perhaps the fish was bullied by another fish in the community fish tank. If that’s the case, then you’ll need to check to see if you’ve put the cory cats in a tank with incompatible tank mates.

Try to look and see if anything appears to be wrong with the fish physically. Does it have any injuries?

If it does, then the fish might not be moving due to being hurt. It might recover over time, but it could also die depending on the severity of the injuries.

3 – Has the Fish Been Infected?

Another thing to consider is whether or not the fish has some type of infection. Sometimes fish will get infected when the water quality isn’t where it should be.

Water quality issues can stress the fish and make them more susceptible to infections. Thus, the first thing you should do is check the water parameters to see if everything is okay.

Note that infections might make a fish appear to be lethargic. This could explain why it isn’t moving.

It’s also possible that the fish might be experiencing swim bladder issues due to an infection. Infections can cause inflammation of the intestinal area, and this will cause the swim bladder to malfunction.

When a fish can’t swim normally, it might choose to just remain motionless. It isn’t uncommon to see fish laying on their sides when something like this happens.

You might need to treat the infection to get the fish better. Clearing an infection up involves giving the fish antibiotics.

If all goes well, then the fish will eventually improve and start moving around normally. Sometimes it isn’t always simple to tell if the fish has an infection or not, though.

4 – Other Types of Diseases

Of course, there are other types of diseases that might make a fish stop moving around much at all. Some types of illnesses have been known to make fish sluggish.

If you suspect that your fish is sick, then you’ll want to try to determine exactly what is wrong. Doing this is often about paying close attention to the symptoms and trying to match things up with known diseases.

It’s also pertinent to monitor the condition of the tank. Remember that these fish don’t do well when the pH balance is thrown off.

If all else fails and you don’t understand what is going on, then it might be wise to consult an exotic veterinarian. A vet can diagnose the issue and help you determine how to best help the fish.

5 – Heightened Nitrite Levels

Heightened nitrite levels might wind up making the fish get really ill. Cory catfish are susceptible to nitrite poisoning.

If the water in the fish tank is dirty, then there’s a good chance that the nitrite levels are unacceptably high. This has the potential to kill the fish.

Hurry and check the condition of the water so that you can determine what is happening. This will allow you to make necessary changes in an effort to save the fish.

It’s not guaranteed that the fish will survive, though. Cory catfish can die suddenly due to elevated nitrite levels.

6 – The Fish Could Be Dead

If the cory catfish is truly motionless and you can’t get a response, then it might be dead. Try to check to see if its gills are moving at all.

When the gills aren’t moving, it’s likely that the cory catfish has perished. It could have died for a number of different reasons.

As mentioned above, cory catfish can die rather suddenly due to high nitrite levels in the tank. This is why it’s imperative to keep an eye on the water quality by doing regular testing.

You also need to endeavor to maintain the tank the right way. This means cleaning the fish tank and doing regular water changes.

Try to figure out what is wrong in the tank so that you can save your other cory catfish. You don’t want the other fish to die.

It can be frustrating to lose a fish in this fashion. Try to think of it as a learning experience so that you can do a better job caring for the other fish in the tank as well as any future fish that you might purchase.

Final Thoughts

You’ve learned about many things that might cause a cory catfish to stop moving. Some of the options might be nothing to worry about, but most are going to be causes for concern.

If you’re lucky, the fish will simply be resting and will start moving soon enough. Cory catfish often take naps for several minutes at random times of the day.

You’ll find them laying on their sides and worry due to not knowing that this is normal for them. Then they go about their business as if nothing happened.

If this isn’t the case, then something is probably wrong with the fish. It could be injured in some way or it might even be sick.

You’ll have to try to pay attention to the fish to see what’s wrong. It’s also a good idea to check the water to see if you have elevated nitrite levels.

Hopefully, you’ll be able to nurse the fish back to health whether it has an infection or if it’s dealing with something such as swim bladder issues. It’s also possible that the fish might be dead.

When the fish is truly not moving, you have to consider whether it is alive or not. You’ll need to look to see if the gills are moving at all to determine if it has perished or not.