Betta Fish Laying on Bottom of Tank or on Side: Is It Normal?

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Last Updated: September 4, 2023 by Flora Gibbins

Betta fish has a lively and colorful personality. It is responsive to the surroundings and often swims excitedly. Hence, when it is inactive, the initial reaction of most people is to panic. 

Is betta fish laying on the bottom of the tank normal? Why is it not moving? Should you be concerned? 

There are several reasons bettas might lay on the bottom of a tank, some of which are common and harmless and some can be signs of stress or illness. Learning to recognize which is which can help you solve any issues your betta might be having.

Reasons Why Betta Fish Is Not Moving 

Betta Fish Laying on Bottom of Tank -

Seeing a betta fish not swimming is terrifying if you are unaware of the causes. You might think that it is dead. However, the lack of movements is not necessarily a sign of death. Instead, it can be something as simple as sleeping to something more serious like poisoning. 

1. Sleeping Betta Fish

One of the most common reasons for a Siamese fighting fish on the bottom of the tank is that it’s sleeping. Betta fish often enjoy laying on their sides while resting. It’s comfortable for them, even though it looks like very strange behavior to most aquarium keepers.

A betta with a good appetite, plenty of energy, and hasn’t been seen gasping for air but is on the bottom of the tank is often just taking a nap. If you’re not sure whether your betta is simply tired, observe the fish closely for a few days and watch for any signs of stress or illness.

Bettas like a place to rest their (usually) large fins. You can also add a resting place above the fish tank’s bottom to check if your betta fish is just laying on its side to sleep.

When offered a broad-leafed plant, a hammock, or a similar betta fish accessory, many fish will switch from lying on their side to the bottom of the tank to laying on their side in the new resting place. This is usually a sign that your fish is fine.

2. Older Bettas Like Resting at the Bottom

Another common (and harmless) answer to the question, “Why is my betta fish at the bottom of the tank?” is that the fish is old and is lacking in energy. Older betta fish may not have the stamina to swim around the tank as much, and they may take a brief break by laying on their side at the bottom of the tank.

As bettas age, you may want to provide more resting places. Bettas also prefer a slow, gentle water flow, and this is particularly important for older fish.

3. Ammonia Poisoning

A betta laying on bottom of tank can be nothing to worry about. However, if your betta fish is not eating and also laying at the bottom, there could be a problem.

Changes in the water temperature or chemistry can often cause this behavior, and the most common issue is ammonia poisoning.

It’s relatively easy to check for poisoning. First, observe your fish and look for gasping or any sign that your fish is breathing heavily. Next, use an aquarium test kit to check the ammonia levels in the water. The ammonia level should be at or near zero.

If the ammonia level in the tank is too high, you can perform a partial water change. You can change about half of the water in the tank, but it may be best to remove about 25 percent and then repeat the process over the next few days. Continue to monitor the chemical levels until they’re once again balanced.

You can also reduce ammonia levels by cycling your aquarium before you add any fish. Keeping the tank clean, avoiding overfeeding, and investing in a good filter that will perform chemical, mechanical, and biological filtration can also help. A water conditioner can also be added as a temporary fix.


4. Nitrate Poisoning

Nitrate poisoning is an issue caused by a chemical spike in the aquarium water. Fish with nitrate poisoning may be breathing heavily and look pale or discolored. They may also seem lethargic and maybe on their side but not dead.

Test the water to check for nitrate spikes. This number should also be close to zero but should be under 20 ppm. If the nitrates are too high, perform a partial water change and add a cycled filter to the aquarium.

5. Swim Bladder Disease

Swim bladder disease is a common fish illness and it’s often the reason why your betta fish is laying on its side.

Swim bladder disease refers to a condition that means the swim bladder can no longer function correctly. This makes it hard or impossible for your betta to swim around the tank. Some fish with a swim bladder problem might float near the top, but others will lay at the bottom.

Swim bladder disease is often caused by overfeeding or a fish’s inability to digest its food properly. To help a fish with swim bladder disorder, offer it small pieces of thawed green peas or daphnia fish food, both of which are high in fiber. You can also refrain from feeding your fish for a few days. Once it feels better and has passed whatever was bloating it, a betta that was laying on its side should soon return to swimming normally.

To avoid swim bladder and constipation issues, avoid overfeeding your fish. Only feed once or twice each day, and only offer four to six pellets per feeding.

6. Small Aquarium 

Another common culprit for betta fish not moving is the size of the aquarium. It can be too small for the fish. The right aquarium size depends on the number of betta fish

If you only have one betta fish, the aquarium should hold three to five gallons of water. For every inch that the betta fish grows, you need to add another gallon of water. Meanwhile, if you will add community fish, adding more water is necessary as well. 

Bigger aquariums are better for betta fish. It will provide them more room to move, which is a must since they are very active. A small tank restricts their movements. More so, a smaller tank also means that bio-load builds up quicker, which is poisonous for bettas.

While a bigger tank minimizes the chances of a betta fish laying on the side but not dead, it also prevents being too aggressive. Because they will have a bigger territory, bettas don’t have to fight with other fish to claim their space. 

7. Temperature Fluctuation 

A fluctuating temperature is a threat to betta fish. The chances of having a betta fish not eating and laying at the bottom are higher when the tank water temperature goes up and down. Keep the temperature at 75 to 80 degrees Fahrenheit

As tropical fish, bettas experience a cold shock when water temperature decreases rapidly. It results in a variety of behavioral and physiological consequences, including lethargy. Being cold-blooded, bettas absorb the water’s warmth instead of generating body heat. Hence, a sudden decrease in water temperature will make it difficult for them to move. 

Meanwhile, hot temperature shock is another common cause of betta fish not moving. Nonetheless, the effect isn’t as severe as a cold shock. You will notice erratic swimming, heavy breathing, and inactivity if the water temperature rapidly increases, which is too hard for the betta to deal with. 

8. Wrong pH 

When you see betta fish laying on the side at the bottom of the tank, it can be because of poor water quality. Among others, a common suspect is a wrong pH. 

Bettas thrive best in water with neutral pH of 7.0. Tap water is a great option, which has a pH level of 6.5 to 7.5. 

A tank with the wrong pH can kill your betta. It can suffer from a condition known as pH shock. While it can kill the fish instantly, it can also be a slow death. In the case of the latter, the fish will demonstrate weakness, including limited movements. It might first settle at the bottom of the tank before it dies. 

9.   Lack Of Filter 

A betta laying on the side or bottom of the tank can be an indication that your aquarium does not have a filter. The right filter gets rid of toxins and bacteria that can harm your fish. 

Without a filter, chemicals will build up. This will result in ammonia and nitrate poisoning, as I earlier mentioned. Poor water conditions because of the lack of filter can also cause fin rot and bacterial infection. 

Having a filter, however, does not suffice. At times, you will notice a betta fish sitting on the bottom of the tank even with a top-notch filtration system. It’s because the filter’s current is too strong, so you might need to adjust its settings. 

A current that is too strong will eat up your betta’s energy. Imagine yourself swimming in a sea with huge waves. It’s a struggle, right? That is exactly what bettas can experience as well. Instead of fighting the movements of the water, they might decide to just not move. 

Attaching a sponge filter is one of the quickest solutions for reducing the current that the filter generates. You can also redirect the flow of water to the ornaments in your aquarium instead of directly hitting your fish. 

10. Improper Eating Habits 

A proper diet is essential for a healthy betta fish. Nonetheless, take note that too little or too much food is bad for their health. It is another leading cause of a betta fish laying on the bottom of the tank. 

Feeding bettas with too much food results in bloating. Like humans, they cannot move a lot when they are full. Hence, they will stop swimming, lay at the bottom, or settle on the side of the tank. 

On the other hand, feeding the fish with too little food means that they won’t get the nutrients that they need. Without proper nutrition., their energy suffers. In turn, it limits their movements. 

11. Lack Of Habitat Features 

An aquarium’s habitat features serve more than just decorative purposes. They are also influential in creating an ideal environment for bettas to thrive. 

Bettas love to have plenty of hiding spots, and a betta laying on the bottom of the tank may be stressed if there aren’t enough places to shelter in.


Add more plants to the aquarium or place a small cave or house structure in the tank. Making your betta feel safe and secure can help it remain healthy and usually stop a betta fish from lying on the tank’s bottom.

12. Wrong Tank Mates

Bettas are also known as Japanese or Siamese fighting fish. The name itself already gives you an idea of its aggressive behavior. Despite such, however, it can coexist with other fish in a tank, though you must be picky. 

Avoid bigger and more colorful fish, which can be intimidating for bettas. Nibblers are also a no-no. It is best to go with bottom feeders as they have minimal impact on bettas. 

You should also not have two male betta fish in one tank. Having two males is a sure-shot formula for disaster as they will end up fighting. 

While it is common for bettas to attack and fight once they are threatened, this may not always be the case. At times, they are also afraid. They will hide or remain emotionless. Instead of being aggressive, your betta may instead end up not moving if it lives with a more aggressive aquarium fish. 

13. Death 

This is the worst-case scenario for a betta not moving. No one wants to have a dying betta fish, but the reality is that your fish will reach such a stage. 

On average, the lifespan of a betta fish is two to four years. It depends on the conditions of the environment, including water quality and temperature. Proper care and maintenance will help the fish live longer and have a better quality of life. 

To check if the betta is dead, one of the first things to look at is the gills. Look for indications that it is still breathing, even if it is not moving on the bottom or side of the tank. The discoloration is also apparent in a dead betta. 

You can also tap the betta tank lightly and watch out for any reaction from the fish. Even the slightest movement is proof of life. Even a sick betta will move when you tap the glass. 

Best Practices To Prevent Betta Fish From Not Moving 

Avoid having a betta fish laying on the side or bottom of your tank. Below are some of the best practices to keep it active: 

  • Observe the fish and check for signs of illness, such as lethargy or lack of appetite
  • Use medication or other remedies to clear up any conditions, such as swim bladder disease
  • Offer the betta a resting place
  • Check for chemical spikes and ensure that the water chemistry is balanced
  • Feed the fish with the necessary nutrients while avoiding under or over-feeding
  • Add more hiding places or move the betta fish to a larger tank to help reduce stress
  • Avoid overstocking the aquarium with ornamentals as it can restrict movements 
  • Be mindful of the tank mate of bettas, avoiding fish that is too aggressive
  • Keep the aquarium water between 75 and 80 degrees Fahrenheit


What fish can coexist with bettas? 

Some of the best options for a betta’s tank mates are cory catfish, guppies, glass catfish, and blue gourami. They can create a peaceful and ideal environment, which will prevent the betta from laying on the side or bottom of the tank because it is scared. 

Is it normal for a betta fish to say still? 

Yes, it is normal for a betta fish to stay still. It is a common behavior, but in many instances, it is associated with several problems, such as water parameters, old age, and sick fish. 

What are the differences between a sleeping and dying fish? 

When you see a betta fish laying on the bottom of a tank, it can be sleeping or dying. The best way to tell the difference is to look at its appearance. If you can see dark spots or other forms of discoloration, as well as signs of difficulty breathing or a struggle, it is most likely dying and not just sleeping. 


Have you ever stared at your tank and wondered why is my betta fish not moving? It can be dead, but most of the time, the lack of movement is nothing more than normal betta fish behavior.

It’s best to double-check, though, so look for any signs of illness or stress and test the aquarium water to make sure it’s within the proper chemical range and temperature. Working quickly to resolve any issues will ensure an energetic and healthy fish.

Is there anything else that you would like to share? Do not hesitate to leave a comment below. 


7 thoughts on “Betta Fish Laying on Bottom of Tank or on Side: Is It Normal?”

  1. Help! My sons fish has not eaten in days and is laying on the bottom of the tank. I cleaned the tank this weekend, and I noticed him gulping for air in the container I use while cleaning. How do I get him to eat and NOT DIE??

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