Why Is My Fish Swimming Fast Back And Forth?

Are you looking at your fish tank wondering, “Why is my fish swimming fast back and forth?”

It’s a sight you don’t want to see as a fish owner.

Unfortunately, millions of people worldwide mention this as being a problem inside their fish tank. The reason often has to do with stress, but what causes a fish to get stressed?

By understanding the root cause, you can take immediate action and help improve how the fish tank is maintained.

Here is a detailed answer to the question, “Why is my fish swimming fast back and forth?” along with a comprehensive assessment of what you can do about it.

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Why Is My Fish Swimming Fast Back And Forth?

Unclean Fish Tank

The first concern is going to be the water inside your fish tank.

However, you should also pay attention to the fish tank and its cleanliness too. A lot of fish tank owners assess the water condition, use a water changer, and hope for the best.

While this is effective, it’s important to also clean the fish tank when you get the opportunity to do so. When a fish tank isn’t clean, fish are known to start displaying erratic behavior and becoming stressed with their environment.

It’s best to assess whether or not there is unwanted algae growth in the fish tank or gravel has started to spread near the bottom. In some cases, you will also have uneaten fish food lingering in the water too.

In these situations, you have to take action right away and make sure it is effectively removed.

Why Is My Fish Swimming Fast Back And Forth

Improper Fish Food

When asking “Why is my fish swimming fast back and forth?” sometimes it comes down to the fish’s diet.

Is your fish eating the right type of food? Is the food organic and easy to digest?

These are questions all fish owners need to ask when something like this happens. Remember, one of the more prominent variables a fish owner controls is what their fish eats. When the dietary intake isn’t on par then everything else starts to fall apart.

Take the time to look at what you are feeding your fish because it’s essential.

Giving your fish the wrong food can heighten its stress and cause the fish to showcase erratic behavior such as swimming back and forth.

It’s recommended to go with organic fish food that’s ideal for your fish. This food is going to offer a good amount of nutrients and will remain easy to digest year-round.

You should also take the time to see whether or not your fish has been eating during previous feedings.

When a fish stops eating, you will notice a good amount of food being leftover in the water. This can be a sign of two things – overfeeding or feeding the wrong type of fish food.

In both circumstances, you will have to make a quick adjustment to ensure the fish stops pacing back and forth in the fish tank.

Irregular Water Temperature

When the fish tank’s temperature starts dropping rapidly, this can cause quite a bit of stress for the fish.

It’s important to regulate the water temperature using a state-of-the-art aquarium heater such as the Aqueon Pro 50W Heater.

When testing the water, it’s recommended to use a thermometer and take regular readings. While doing this, you should have a journal by your side to jot down what the thermometer displays.

If the temperature continues to fluctuate, it can have a devastating effect.

This is why it’s important to take the time to understand how the water is inside the fish tank. There are times when the water temperature rapidly fluctuates causing the fish to panic.

To alleviate this worry, it’s best to use a good aquarium heater that can regulate temperature. This will save you quite a bit of trouble and is going to ensure the fish remains safe.

When you are asking questions such as “Why is my fish swimming fast back and forth?” it’s often going to come down to something like this. You have to keep tabs on everything associated with the fish tank including the water temperature.

Remember, you can also control the room temperature inside your house. If it is too hot or too cold in one part of the house, take the time to make adjustments using your thermostat. You can even move the fish tank to another part of the house.

Why Is My Fish Swimming Fast Back And Forth

Low Oxygen Levels in the Fish Tank

When the oxygen levels in your fish tank start dropping, the fish will start to swim erratically. This can immediately cause a tremendous amount of stress.

This is why regulating the fish tank’s oxygen levels is key using a quality air pump such as Tetra Whisper Air Pump.

Your focus should always remain on seeing how the fish is doing inside a fish tank. Unfortunately, a fish can start to feel uncomfortable when there’s not enough oxygen being pumped into the water. This happens due to how modern fish tanks are designed.

Even with a good fish tank, you are not going to be in good shape unless you take the time to set up a great air pump.

This is key information for anyone serious about the amount of stress their fish is under.

Focusing on whether or not there’s enough oxygen in the fish tank can help stabilize a fish’s condition inside immediately.

In the natural world, a fish is going to be swimming through a naturally oxygen-friendly environment. This means airflow allows the water to move (i.e. create currents) which keeps the water fresh. Inside a fish tank, you are not going to be able to recreate this organically. It has to be done using a state-of-the-art air pump.

If your fish tank doesn’t have an air pump then this may be the reason for your fish’s discomfort.

This is an important change fish owners need to make when it comes to keeping their fish as healthy as possible. Focus on this and watch as the oxygen levels begin to rise.

Wrong Type of Fish Tank

This is a major issue but it does happen from time to time.

You have to think about your fish and what type of environment it’s supposed to swim in. When the wrong type of fish tank is purchased, you end up restricting the amount of space a fish has to swim in.

This can put a tremendous amount of stress on the fish as it expects to be able to roam around freely.

When this happens, you will start to notice odd behavior such as the fish swimming along the glass back and forth. Instead of assuming this problem is going to go away on its own, you have to take action immediately.

Start by changing the fish tank and finding one that is suitable for your type of fish. This is the only way you are going to alleviate the problem.

If you continue to use the wrong type of fish tank, it is going to worsen the problem until your fish shuts down.

This is similar to most animals when they are put in the wrong type of environment. It’s difficult to survive in the wrong environment even if everything else is okay such as the amount of food they are eating.

Final Thoughts

“Why is my fish swimming fast back and forth?”

This is the question people have and it all comes down to finding the root cause. Whether it has to do with an unclean fish tank, improper diet, or being put in the wrong aquarium, you have to focus on making adjustments right away.

Take the time to learn more about these causes and make sure your fish isn’t under stress all the time.

If this problem is prolonged, it can have a devastating impact on the fish’s lifespan.

For more information on other fish-related topics, please take the time to go through the following articles – Reasons for why a betta fish stops eating, ways to reduce ammonia in a fish tank, how to remove fish tank odors, and ways to clean algae from a fish tank.