Why Is My Betta Fish Not Moving? 4 Common Reasons Why

Betta fish are popular among aquarist due to their vibrant colors and active personality.  These fish will keep you entertained for hours.  However, there are some instances where you approach them and they seem motionless, just drifting around the aquarium.  Most people will start to panic when seeing the Betta fish like this.  The first thing that comes to mind is the fish have died.  Before jumping to that conclusion, there are a couple of reasons why the Betta fish is not moving.

Why Is My Betta Fish Not Moving?  The 4 main reasons could be they are sleeping, stressed due to their environment, sick due to an ailment, or have died. 

Below are the most common reasons why your Betta fish may seem motionless and what you can do and what you should not do.

Your Betta Is Better At Sleeping

Betta fish are one of those fish that sleeps often, especially during the day.  During the day,  they may frequently nap often at 2 to 5 minutes per nap session.  When they are sleeping, you may notice the Betta fish floating around the tank lifeless.  Sometimes, you may see them wedged between plants and ornaments. Betta fish are known to sleep in various and odd places so it’s important to know if they are just sleeping or not moving due to stress or illness.

Betta will usually wake up when you get near the aquarium.  From being awake from their nap, they will move sluggishly at first.  There’s nothing to be alarm about this.  However, if this sluggish movement continues longer, there may be something wrong with them.

Instead of taping on the aquarium glass which could startle them, just check for the gill and mouth movement. While the fish is sleeping, their gills will slowly close and open. This goes the same for their mouths. Read more on the topic ‘Do fish Sleep?

Your Betta Is Stressed Due To His Environment

Betta fish are hardy and can survive under different living conditions, but they still need the right conditions to thrive. A Betta fish that is stressed with their environment will not move much. The main environmental concerns affecting Betta fish would be aquarium size, tank mates, water conditions, and water temperatures.

Aquarium Size

There are many opinions on the right aquarium size for Betta fish. From my personal experience, Betta needs plenty of swimming space. The larger the aquarium, the better it is for them.

An aquarium that is too small will cause them to be stressed. In their natural habitat, Betta moves around often in search of food. They rarely will stay in the same location all the time.

When they are placed in a small aquarium like a glass bowl, they won’t have too much of a room to move. Much of their movement will be swimming in a circle. Betta fish are smarter than we think. When the aquarium is small, they will move very little. When they don’t have much room to move, they will begin to get stressed. This stress could lead to them being sick caused by not eating.

Getting the correct size aquarium is crucial to the health of the fish. A Betta fish require something around 5-10 gallons of water, which is plenty of space to swim.

Tank Mate

When it comes to friendliness, Betta fish isn’t one of them, especially the male fish.   Male Betta is known to be very aggressive at each other.  They will fight each other till one dies if put in the same tank.  This is the reason why most aquarium should only have one Betta fish in each.

As for other fish, Betta will usually get along with other tropical fish species.  Below are the fish that are compatible with Betta in the same tank:

  • Neon Tetras
  • Plecostomus
  • Cory Catfish
  • Zebrafish
  • Hatchetfish
  • Clown Loach
  • Mollies
  • Rasboras
  • Swordtail
  • Guppies
  • Other Betta Fish (Female only)

However, each Betta fish has its temperance.  Even though they are known to get along with other fish, the one you have, may not.  Usually, when they are put in the same tank with another fish they don’t like, the Betta will either start chasing the fish or go into hiding.  If you see any of this behavior, it’s best to put the Betta fish in an aquarium by themselves.

If you don’t remove one or the other, Betta fish will begin to get stressed.  When they are stressed due to another fish, they will spend most of their time hiding and being motionless.  Prolonged time in hiding will cause them to become ill due to not eating or scared of the other fish.

Water Quality

Water condition is very crucial to the health of your betta fish. Good water conditions will help keep your betta fish from being stressed as well.

Betta fish are known as hardy fish and can survive in most water conditions. However, prolonged time in bad water conditions will deteriorate their health.

For betta fish to be healthy and not be stressed, they need water with a “neutral” pH of around 7.0.  If you’re planning to use tap water, it has a pH of between 6.5 to 7.5. This pH range is fine for the betta. However, if the pH is lower or higher than the recommended range, you’ll need to adjust it as soon as possible. One simple way is to get a pH testing kit and test the pH balance in the water. Depending on the reading, you use a water conditioner to adjust the pH balance to the acceptable range.

Never use distilled water! Distilled water has had all its minerals removed. Betta fish need these basic minerals to stay healthy.

In addition to keeping Betta fish healthy and from being stressed, you’ll need to change the water often. If it’s in a fishbowl, you’ll need to change the water 50% of the tank water weekly. For betta living in a filtered tank, you’ll need to change the water 15-20% of the tank water weekly.  Doing so will ensure the water is removed from ammonia and other toxins.

Water Temperature

Most people know the Betta fish are hardy and can live in almost any environment. One thing that most people don’t know is the water temperature and why it’s important to a Betta fish. Believe it or not, the water temperature has a huge effect on the movement of the Betta fish.

When the water temperature is high, the fish’s metabolism will increase and make them hyper.  The fish will swim around the tank fast, which isn’t healthy for them.

On the other hand, the colder temperature in the aquarium will cause the Betta fish to become sluggish, sleepy, and have a loss of appetite. When the water is too cold, their metabolism will slow down and there will be less movement from the fish.

Also, colder than the recommended temperature can also be bad for their health. Prolong exposure to cold temperatures can cause the Betta fish to become ill.

To prevent stress and health issues for the Betta fish, the temperature should be set correctly for them at all times.  The best water temperature for betta fish is between 76° and 80° F (24.5° and 26.5° C).   Temperature in the upper 70° Fahrenheit range is best for them.

Your Betta Is Sick

Betta fish not moving could be due to an illness.

There are a few diseases that are common to the Betta fish. These are fin rot, dropsy, and tumors. All of these could cause the fish to become ill and not move around.

Out of all the diseases common to Betta, there is one in particular that will make them incapable of moving. This disease is the swim bladder disease, which is commonly referred to as SBD.

Swim bladder disease is a common ailment among Betta fish. They are prone to this disease in a home aquarium mainly due to poor water conditions. Poor water conditions can be caused by many things such as not changing the water frequently, poor water filtration, and polluted water due to uneaten foods.

In addition to poor water conditions, SBD can be caused by constipation, parasites or bacterial infections, and enlarged organs.

The symptoms you’ll see are swimming sideways or upside down. For the most part, Betta fish with swim bladder disease will lay at the bottom of the aquarium motionless, except for gill and mouth movement.

SBD can easily be prevented by making sure to maintain high-quality water, feeding only high-quality food, and making sure there is no uneaten food left over.

If the Betta fish do have SBD already, you’ll need to treat it right away. To treat the fish, simply raise the aquarium temperature by a couple of degrees, and don’t let them eat for a couple of days.  After a couple of days, feed them daphnia which will help them poop easily.

Your Betta Has Passed Away

Betta fish have a lifespan of an average of 5 years.  Some can live much longer than that though.

When the fish die, they are either found floating lifelessly around the aquarium or laying still at the bottom. If you find your Betta in this position, this is a great probability that they have died.

Before jumping to the conclusion that the fish is dead, examine the fish first. Check their gill and mouth for any movement. If you don’t see those body parts moving, don’t assume the fish is dead yet. Some Betta fish will sleep with the gill and mouth not moving for about a minute.

Another thing you can check is the color of their skin. Live and healthy Betta fish will have bright, vivid, and shiny coat. Betta fish that are dead will have a dull pale skin color.

Lastly, tap on the aquarium glass to try to awake the Betta fish. Most of the time, the fish will be startled and wake up. If tapping the glass and see no movement, it’s a good indication that the fish is dead.

If the Betta fish is in a tank with other fish, you may want to remove it as soon as possible. Dead fish release dangerous toxins that could kill other fish in the tank.


The above reasons are not all of why your Betta fish is not moving, but they are the most commons for Betta fish.  It may seem awkward that a fish you used to see be so active and one day, they seem motionless and not moving at all.   Before you start worrying, check their gills and mouth for movement first.  Most of the time, they’ll just be resting and waiting for you to come by to show off.

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