Why Do Tetras Swim Upside Down? (Is It Normal For Tetras?)

Image of tetras swimming together

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Tetras are beautiful fish that liven up aquariums with their incessant activity. You will find them darting across the tank and performing acrobatics all the time. However, if you ever notice a tetra swimming on its side or upside down, pay close attention. It’s not normal for tetras to swim in this manner and means that the fish needs help. So, why do tetras swim upside down?

There are two main reasons why a tetra may swim upside down: sickness or shock. Unfavorable conditions like a change in the water parameters or stress caused by the introduction of a new fish can cause shock. Infections and disorders such as swim bladder disorder can also cause the same condition.

Although tetras are low-maintenance fish, they are vulnerable to stress and sickness. Swimming upside down is a clear sign of distress that you should not ignore. If you can recognize the cause of this condition and attend to it, you can help your tetra recover. So, let us explore the causes of this problem and the solutions for it.

Is It Normal For Tetras To Swim Upside Down?

Certain fish like catfish and lionfish swim upside down all the time. For these fish, swimming upside down is normal behavior and not a cause of concern.

However, it is abnormal for most types of other fish to swim on their side or upside down. Tetras do not usually swim this way. So, if you find your tetra swimming upside down, you should be concerned. This abnormal behavior is either caused by shock or sickness.

One of the most common conditions that cause a tetra to swim upside down is swim bladder disorder. It is a condition when the swim bladder of the fish becomes bloated. As a result, the buoyancy of the tetra is affected, and it flips over on its back.

What Causes A Tetra To Go Into Shock?

Tetras are very sensitive to environmental changes. Changes in water parameters and lighting stress them. Even the introduction of new fish into the tank affects them.

If your fish starts swimming upside down, check for any recent aquarium changes that may have triggered this behavior. Did you recently change the water? Or has it become too dirty?

Another possible cause could be a change in the lighting setup. Consider whether you have recently increased or decreased the exposure of the fish to lights. If you added a new fish to the aquarium, it could also cause your tetra to become stressed. You may like to check if the new fish is bullying your tetra or competing for food and resources.

In most of these cases, dimming the aquarium lights should help your tetra adjust to the problem.

Finally, tetras may temporarily swim with their nose down and tail up when you introduce them to a new tank. Once they are acclimatized to the new arrangement, they will resume swimming as usual.

What Is Swim Bladder Disorder In Tetras?

The swim bladder is a buoyancy organ in bony fish like tetras. It has thin walls and is filled with gas. The purpose of this organ is to help the fish stay afloat. It allows the fish to swim at a chosen depth and neither float upwards nor sink.

Swim bladder disorder is a condition where the swim bladder cannot perform its normal function. Swim bladder disorder makes the bellies of tetras look bloated or distended.

It usually happens due to digestive problems, like when the fish is constipated, gulps air, or overeats. Organ conditions like fatty liver deposits may also cause it. In some cases, parasites like bacteria can also cause swim bladder disorder.

Since the swim bladder plays an important role in keeping the fish buoyant, this disorder affects the proper movement of the fish. The tetra fish may float on its sides, upside down, sink to the bottom, or float at the top of the tank when affected.

You can suspect this condition if you see your fish struggling to stay upright and flipping over as though it has lost control.

Tetras affected by the swim bladder disorder are often unable to feed properly. They may display no appetite at all. You may also notice that the fish is unable to swim to the surface of the water to reach food.

Related Further Reading:

What Causes Swim Bladder Disorder In Tetras?

Swim bladder disorder in tetras is mostly caused by improper eating and digestion. To fix the issue, you should first identify the underlying cause.

Here are some of the most likely causes of swim bladder disorder in tetras.

1. Gastrointestinal problems put pressure on the swim bladder.

The following problems can cause gastrointestinal issues in tetras:

  • Normal fish food consists of freeze-dried pellets or fish flakes. This type of food tends to expand once it becomes wet. When the tetra feeds on it, it can cause the stomach of the fish to become bloated.
  • Some fish gulp in air with their food. It can cause bloating and swelling of the stomach.
  • Certain food choices can produce gas and cause the gastrointestinal tract of a fish to enlarge.

When the gastrointestinal tract becomes gassy, it pushes on to the swim bladder. Compression of the swim bladder presents buoyancy problems.

2. Low water temperature.

When the ambient water temperature is low, the digestive process in a tetra fish slows down. Sluggish digestion leads to bloating and swelling of the digestive tract. This, in turn, affects the swim bladder.

In all these scenarios, you can reverse the condition by changing how you feed the fish. You can also improve their digestive ability by increasing the temperature of the surrounding water.

Related Further Reading:

How To Treat Swim Bladder Disorder In Tetras?

If your tetra fish shows symptoms of swim bladder disorder, you can try the following remedies.

  • Do not feed the fish for three consecutive days. It will give the fish enough time to digest what is present in its gastrointestinal tract.
  • When you resume feeding, reduce the amount of food. Soak pellet or freeze-dried food in water before feeding the fish. It will prevent the food from swelling up inside the digestive tract.
  • If the disorder is caused by constipation, you can try feeding a cooked pea. Remove the skin of the pea and feed it. It will help to release gas and enable the fish to recover faster.
  • If parasites like bacteria cause the disorder, you may have to administer suitable medication. Check with a vet to find the right medicine for the condition.
  • Epsom salt can also be effective in some conditions. You can use one-eighth of a teaspoon per five gallons of water to treat your tetras.

While your tetras are suffering from swim bladder disorder, it is a good idea to reduce the tank’s water level and water flow. It will make it easier for them to move around.

Interesting Further Reading:

Why Do Neon Tetras Swim Upside Down?

The swim bladder regulates buoyancy in neon tetras. The fish will swim upside down when the swim bladder is impacted.

Digestive issues, physical conditions, or parasitic infections can cause swim bladder disorder. Overfeeding, gulping of air, or constipation can lead to digestive problems like bloating that in turn affect the swim bladder.

When the digestive tract is affected, the swim bladder gets compressed. This affects the ability of the neon tetra to stay afloat.

Parasites or congenital conditions may also cause swim bladder disorder in neon tetras.

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