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4 Common Causes of a Discus Fish Swimming Sideways

4 Common Causes of a Discus Fish Swimming Sideways
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.

Discus fish are so pretty and many people love having them in their aquariums. You might think that discus fish are some of the most gorgeous fish you’ve ever owned.

They can certainly be the pride of your aquarium if you care for them well. Sadly, discus fish are known for being a bit on the delicate side.

Often, these fish will experience issues when the water quality isn’t kept very high. So you must pay close attention to tank maintenance.

If you’re putting in the effort, you’re going to be concerned when you see that your fish are acting a bit odd. Are your discus fish starting to swim sideways?

What does it mean when these fish swim sideways? Continue reading to get to the bottom of this situation.

Why Do Discus Fish Lay on Their Side?

When you see a discus fish laying on its side you should be concerned. This isn’t normal and it’s a sign that something is amiss.

There could be several things that are happening that are causing the fish to lay on its side or to swim sideways. It’s important to consider each possibility so that you can troubleshoot the situation.

1 – Discus Plague

There is a sort of controversial illness known as discus plague that you should be aware of. Some people say that this isn’t a real disease while others swear that it is.

Fish that get this disease are said to go through color changes and experience appetite loss. They also swim in an off-balance fashion.

The fish might swim sideways or it might look unstable when it’s swimming. When you see a fish that shows signs of discus plague it’s recommended to transfer it to a quarantine tank.

You don’t want it to infect the other fish in the tank. You can contact a veterinarian for treatment advice, but not a lot is known about this condition right now.

There is no true cure right now. This might change in the future, but hopefully, this isn’t what is wrong with your fish.

2 – Swim Bladder Disorder

One of the most common reasons why fish swim sideways has to do with swim bladder malfunctions. The swim bladder is an organ that controls buoyancy in fish.

When the organ isn’t working properly it’s difficult for fish to swim. They can’t remain upright and will sometimes swim in unusual ways.

You might see fish swimming sideways or even upside down. When this occurs, it’s happening because the swim bladder cannot work normally.

Something is keeping the swim bladder from working. This organ is a gas-filled sac that inflates and deflates as necessary.

It can be obstructed when fish are dealing with abdominal inflammation or when they’re bloated. So you might need to treat the fish for an infection or help them to solve constipation issues.

3 – Problems With Water Quality

Water quality issues can harm your discus fish in so many ways. These are fish that are delicate when it comes to water parameters.

The water parameters need to be kept in check or they will struggle to stay healthy. Discus fish become stressed easily when the water parameters are thrown off a bit.

For this reason, it’s best to focus on regular tank maintenance. Some people go so far as to do daily water changes, but it’s likely fine to do a few water changes per week so long as you’re on top of things.

When you’re not doing a great job, the fish might become so stressed that they will start laying sideways. You may even see the fish swimming sideways or acting in other unusual ways.

This occurs when the pH balance of the water is not where it needs to be. Remember that you’re supposed to keep the pH balance between 6.5 and 7.0 to stay safe.

Test the water regularly using pH balance testing kits. Monitor the water temperature to keep things steady.

The temperature in the tank should be between 82 degrees Fahrenheit and 86 degrees Fahrenheit. You don’t want to allow the water to get too hard either since it needs to stay between 1 and 4 dKH.

4 – Overcrowding

Overcrowding the fish tank is a big problem when caring for discus fish. Discus fish are schooling fish and they like to live in groups.

So most people choose to keep six of them in the same tank. Each discus fish needs ten gallons of space, and this means that buying a 60-gallon aquarium is appropriate.

These fish might not do well if you cram the tank with too many fish. Putting them in a community tank is fine so long as there is enough space.

If you’re putting the fish in a cramped environment it can cause them stress. Also, it’ll make it more likely that there will be severe water quality problems due to excessive waste.

Be mindful of this and ensure that you keep discus fish in large enough fish tanks. Otherwise, they might swim sideways and experience other odd health issues.

Eventually, the fish will just die due to stress and water quality problems. Be careful to avoid such situations.

Final Thoughts

When you see discus fish swimming sideways it’s best not to ignore it. It could be that the fish is stressed or sick in some way.

The fish might be experiencing some type of infection. An infection could cause it to have swim bladder issues and this might be what is making it swim so strangely.

Water quality problems are also known to cause these fish to lay sideways or swim sideways. The same can be said about the stress that is related to overcrowding.

Do your best to keep these fish safe by caring for them to the best of your ability. Focus on keeping the water clean and giving them more than enough space.