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Why Is My Clownfish Keeping Its Mouth Open?

Why Is My Clownfish Keeping Its Mouth Open?

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 enjoy caring for your clownfish because they’re such fun pet fish. It’s great to observe them, and you want to do your best to keep them healthy.

Doing everything that you can to help the clownfish thrive should allow them to live for quite some time. However, you might worry a bit when you see the fish acting strangely.

For example, if you are noticing that the clownfish seems to be keeping its mouth open, that’s likely going to worry you. Is this a sign that the clownfish is having trouble breathing in some way?

Keep reading to learn what it means when a clownfish keeps its mouth open. It’ll help you to figure out whether you need to do anything to help the fish or if it’s okay to safely ignore this action.

It Isn’t Normal

The first thing to understand is that it isn’t normal for a clownfish to keep its mouth open all the time. You should observe the clownfish to see whether the mouth is truly open all the time or not.

Is the fish keeping its mouth open a lot? Does it close its mouth sometimes?

Sometimes clownfish will experience a situation known as distended mouth. This can happen when the clownfish experiences some type of physical trauma.

There are a few situations that can commonly cause issues such as this. One of the most common involves a clownfish biting a stinging coral.

Clownfish Near Coral

Another situation where this can occur involves the clownfish getting into an altercation with another fish. In all cases, this issue is caused by physical trauma.

Of course, you don’t want situations such as this to occur. If your clownfish is getting into fights in the aquarium, then you might need to consider whether you chose tank mates properly.

In some cases, you might need to remove fish from the tank and separate the clownfish. You shouldn’t put clownfish in a fish tank with fish that will aggressively bully them.

Will This Go Back to Normal?

This issue can go back to normal in some situations. However, fish tank owners have noted that this problem doesn’t always fix itself.

Whether or not the issue will get back to normal on its own might depend on how severe the physical trauma is. If you’re very worried, then it would make sense to consult an exotic veterinarian for more information.

Outside of that, you can just continue to care for the fish as normal. If the fish seems to be able to eat fine, then you shouldn’t have too much to worry about.

If the distended mouth issue is making it so that the clownfish can’t eat, then that will be much more problematic. Knowing this, you might be a bit more concerned about the clownfish.

Is there anything that can be done to help the clownfish through this situation? Below, you’ll get some advice about how you can help the fish.

Epsom Salt Treatment

Bowl of Epsom Salt

Epsom salt treatment is one of the best ways to try to help a clownfish get better when it’s having issues with its mouth. The distended mouth might get better faster if you can use Epsom salt to treat the fish.

Ideally, you’ll want to move the clownfish to a separate tank. Often, these tanks are referred to as hospital tanks or quarantine tanks.

The fish that aren’t injured don’t need the Epsom salt, and you don’t have any reason to throw off the parameters in your main tank. Set up a quarantine tank for the fish while ensuring that the water parameters are where they need to be.

With this done, you’ll be able to add Epsom salt to the aquarium water. You should add one tablespoon of Epsom salt for every five gallons of aquarium water.

It’s also imperative to use the right type of Epsom salt when doing this. You want to use “USP” grade Epsom salt.

You can repeat this treatment just once if things don’t get better. Don’t continue to do it after that since it could be detrimental to the fish.

This Epsom salt treatment can be helpful to the fish. It’s often used to treat popeye as well as various other fish injuries.

Keep Monitoring Your Fish

Observing Clownfish in Tank

Keep monitoring your fish to see if it gets better. Everything might get better on its own depending on the severity of the injury.

If the clownfish doesn’t appear to be getting better after quite some time has passed, then you might need to consider if something else is wrong. For example, the injury might have been severe enough that it caused the fish to also get an infection.

In this situation, it might be necessary to treat the clownfish with antibiotics. For the best results, you can get advice from an exotic veterinarian so that you can treat your fish the right way.

There could be a situation where a clownfish will have a lifelong deformity, too. An injury could be so severe that it will never truly heal.

So long as the fish is able to live fine, it’s not something that you need to worry about too much. If the fish struggles to live normally, then you might want to consider humane euthanasia.

Final Thoughts

Now that you know more about this topic, it’ll be easier to figure out what to do. Hopefully, your clownfish is going to get better on its own.

It’s likely that the clownfish got injured in some way by fighting with another fish. This has caused its mouth to remain open, and it won’t be able to close its mouth until it starts to heal.

Giving the clownfish Epsom salt as a treatment could help it to get better faster. Just be sure that you’re using the right Epsom salt and that you only use the recommended amount.

If the clownfish doesn’t get better, then the physical injury could be severe. It’s possible that the fish won’t go back to normal, but this doesn’t necessarily mean that the fish won’t be able to go on living.

In the future, you’ll want to be mindful of the type of fish that you put in the tank with your clownfish. It could be that you need to choose better tank mates for the safety of the clownfish.