Bettas are active fish, and an immobile betta is a major concern.
Seeing a lack of movement in your fish is alarming and leaves you wondering: “Why is my betta fish not moving?”
Immobility could mean your betta is sleeping, but it may signal a more serious issue.
A lack of movement does not always mean your betta is on the brink of death, and we’ll help you figure out what may be happening and how to help.
#1 Sleeping or Resting
All living things need sleep and rest to function and stay healthy. Bettas are no different in this regard.
On average, a betta fish sleeps for 8-10 hours per day, usually when it is dark. This is why it is essential to turn the tank lights off at night.
Establishing a consistent light cycle allows your betta to get much-needed rest and prevents disruption of its circadian rhythm.
Sleeping positions vary among betta fish, and it is not unusual for them to sleep on their side.
During the day, you may find your betta resting on a plant leaf or betta hammock. Providing lots of plants and hiding spots allows your betta fish to nap during the day.
Bettas with large fins are likelier to take rest breaks during the day, as they tire easily when swimming.
Betta fish do not have eyelids, so they cannot close their eyes when they sleep. The only way to know if your betta is asleep is to look for signs of gill and mouth movement.
Do not tap on the aquarium glass to check if your betta is sleeping. Betta fish are light sleepers, and startling them awake causes unnecessary stress.
#2 Old Age
A betta fish can live up to five years in captivity with proper care. There are reports of bettas living between 7-9 years, but this is uncommon.
It is often difficult to know your betta’s exact age. Most betta fish are over a year old when you buy them.
Like any other animal, a betta slows down as it gets older.
If your betta no longer zooms around the tank and takes more naps during the day, it is likely to feel the effects of old age.
In addition to frequent napping, your betta will show other signs of aging, such as:
- Fading colors
- No longer making bubble nests
- Curling fins
- Weight loss
Signs of old age occur gradually over several months. If any of the above symptoms happen within a few weeks, they signify something else.
Check your water parameters and examine your betta’s diet to rule out issues other than old age.
#3 Egg Laying
If you have a female betta fish, a lack of movement could signify she is getting ready to release eggs.
A gravid female betta may also develop stripes on her body and have noticeable bloating of the abdomen.
Female bettas can lay eggs without a male present, although they sometimes reabsorb unfertilized eggs.
You must remove unfertilized eggs from the tank before they begin to rot. The rotting eggs will release toxic substances into the water.
Once the breeding cycle is complete, your female betta will resume her normal behavior. When the female does not return to her usual activities, it could signify something more serious.
Check your female betta for symptoms of illness and test your water parameters to rule out other issues.
#4 Laziness
Bettas are lively fish and usually very active swimmers during the day.
You may attribute your betta’s lack of movement to laziness, but something else is usually going on.
Despite what some fish owners may think, there is no such thing as a lazy betta fish.
While bettas slow down as they age, it is not normal for a younger fish to become inactive.
When your betta seems lethargic or is not going after its food, you are likely dealing with a sick fish.
Ensure the tank temperatures and water conditions are at optimum levels, and monitor your fish for a couple of days.
If your betta’s behavior does not improve, check for common signs of illness and seek treatment immediately.
#5 Stress
Stress is often difficult to spot in bettas, but a few signs include:
- Staying on the bottom of the tank
- Frequently swimming to the surface
- Irregular gill or mouth movement
- Lethargy
The signs of stress in bettas often overlap with common illnesses like swim bladder disease. Your betta fish is likely stressed if it has recently gone through a major event, such as:
- Being moved to a new tank
- Recovering from an illness
- Sudden changes in water conditions
- Inadequate sleep
- The introduction of a tank mate
- Eating something hard to digest
Avoid placing your betta in stressful situations. Take extra care when performing water changes to prevent sudden shifts in water temperatures or conditions.
Invest in a light timer if you have difficulty remembering to turn the tank light off at night.
Your betta will be stressed for a few days after introducing a new tank mate. However, once your betta has determined the tank mate is not a threat, it will calm down.
Do not feed your betta hard-to-digest foods like un-shelled peas or large fish pellets.
#6 Boredom
A betta fish with nothing to do will not move around very much.
Mimic your betta’s natural environment as much as possible with lots of plants and hiding places.
Providing your betta with objects to explore will increase your fish’s activity levels.
Change things up by rearranging the tank once a month to give your betta new areas to explore.
Place your betta tank in a room where you spend a lot of time. Your fish will be happy to see you and is more likely to move around when there is activity to keep it entertained.
#7 Improper Feeding and Diet
The culprit may be the fish’s diet when a betta acts sluggish or stops moving.
Betta fish are carnivores and need plenty of protein to maintain energy levels.
Choose high-quality fish flakes and pellets designed specifically for betta fish. Regular tropical fish flakes usually do not contain adequate protein for bettas.
Supplement your betta’s diet with nutritious snacks, such as the following:
- Insect larvae
- Worms
- Daphnia
- Brine shrimp
Always purchase insects, shrimp, and other animal snacks from a reputable source to lower the risk of parasites.
Avoid overfeeding your betta, and remove uneaten food 30 minutes after meal time. Leftover food causes high levels of ammonia in the tank as it decomposes.
Our post on the best food for betta fish has an excellent list of options.
#8 Wrong Water Temperatures
The optimum aquarium water temperature for betta fish is between 78-80° degrees Fahrenheit (27° C).
Hot water decreases oxygen levels in the fish tank, which is unhealthy for your betta.
Colder water temperatures lower your betta’s metabolism and inhibit digestion. As a result, your betta will stop swimming and eating.
Temperature shock is extremely dangerous for betta fish and may lead to death.
Use a separate thermometer to ensure your aquarium heater works properly to maintain the correct temperatures in your tank. Thermostats on aquarium heaters are often unreliable.
Take care when performing water changes. Do not add cold water back into the tank, as this will quickly lower temperatures and may lead to temperature shock in your betta.
Place your betta fish aquarium away from sunny windows or air conditioner vents to prevent sudden temperature fluctuations.
#9 Extreme pH Levels
The best water pH level for betta fish is 7.0, which is neutral.
Maintaining consistent pH levels is crucial for your betta’s health. The effects of extreme pH levels will make your betta too sick to move.
The signs your betta’s water pH is too low include:
- Skin lesions
- Gasping for air
- Low ammonia levels
You must also be aware of the signs of high pH in your betta’s water, such as:
- Algae growth
- Frequent illness
- Abnormal behavior
If you have issues with hard water coming from your tap, consider using bottled spring water to avoid increased pH levels. Never use distilled water, as it lacks vital minerals.
Food particles and urea from fish waste also cause pH levels to rise.
Use pH test strips or an aquarium test kit to check the pH levels in your betta tank at least once per week. Perform 15-25 percent water changes around every two weeks to keep pH levels stable.
#10 Poor Water Quality
Along with stable temperature and pH levels, overall water quality is important for your betta’s health.
Sediment, fish waste, and food particles cause a harmful buildup of toxins like ammonia and nitrites. High levels of ammonia and nitrite are poisonous to betta fish.
Symptoms of ammonia and nitrite poisoning in bettas include:
- Immobility
- Pale coloring or stripes
- Ammonia burns in the gills
- Staying near the surface
- Loss of appetite
If high ammonia and nitrite levels are not corrected, your betta will die.
Levels of ammonia and nitrite should be less than 0.25 ppm (parts per million), but preferably 0 ppm.
Nitrate, a by-product of nitrite oxidation in the nitrogen cycle, is present in all fish tanks.
Since nitrate is not as toxic to bettas as ammonia or nitrite, acceptable levels are higher at 20-40 ppm.
It is almost impossible to get nitrate levels down to 0 ppm because it occurs naturally through the nitrogen cycle.
Regular water changes and removing uneaten food help prevent toxic ammonia and nitrite levels in your betta tank.
Plants in the tank will also filter out toxic particles, along with a quality aquarium filter.
Test your water parameters at least once weekly to ensure ammonia, nitrite, and nitrate levels remain low.
#11 Inappropriate Filter
Filtration is necessary for a betta tank to prevent ammonia and nitrite poisoning. An effective filter also removes harmful bacteria from the water.
But, it is crucial to install a slow filter.
Betta fish have difficulty swimming in strong currents. If the tank filter is too strong, your betta will not be able to swim very well and will stay in one area.
The ideal flow rate for a betta tank filter is between 4-6 gallons per hour (GPH). So, for a 5-gallon betta tank, look for a filter with a 20-30 GPH rating.
An adjustable filter allows you to slow the water current to suit your betta. Sponge filters are an excellent choice for bettas because of their low flow.
#12 Improper Lighting
Aquarium lighting has a significant influence on a betta’s behavior.
When the light is too bright, it overstimulates a betta and causes stress.
Without enough light, a betta becomes confused. Your betta will not understand when it is time to sleep and will have difficulty finding food. This causes the fish to become sluggish or immobile.
An LED aquarium light is the best choice for betta fish. LED lighting produces very little heat, so it does not greatly affect the water temperature.
Some LED aquarium lights even have dimmer controls to adjust the amount of light your betta receives throughout the day.
Invest in a light timer to maintain a consistent lighting schedule for your betta.
#13 Too Many Tank Mates
Overcrowding a tank with too many snails, crustaceans, or other fish restricts a betta’s movement.
Too many tank mates will cause your betta stress, and the fish will not be able to swim freely.
You must have at least a 10-gallon tank if you wish to add snails, crustaceans, or other small algae eaters in with your betta.
A community tank containing your betta and other fish species requires a minimum tank size of 20 gallons.
A 30-gallon tank is needed for a female betta sorority.
#14 Small Tank
Small “betta bowls” and half-gallon tanks are often marketed as homes for betta fish. These types of environments are too small for a betta.
Betta fish need room to swim and explore. Without adequate tank space, your betta has nowhere to go, so it will stay in one place.
Improve your betta’s life by providing a minimum tank size of 5 gallons. A 10-gallon tank is even better and gives your betta ample space to swim and play.
A larger tank keeps your betta active and gives you enough room to add enriching items like plants and hiding spots.
#15 Illness
Illness is one of the most common reasons for a betta to move slowly or not at all.
Cold temperatures, increased ammonia levels, and improper feeding is the major causes of illness in bettas.
Swim bladder disease is a common concern in betta fish, usually resulting from overfeeding and constipation. Bacterial infections may also cause swim bladder issues.
When a betta suffers from swim bladder disease, the fish is tilted to the side and has abnormal swimming movements.
Monitor your betta’s movement patterns for sudden changes. If you notice lethargy, immobility, or a loss of appetite, your betta is likely suffering from an illness.
Diseases like fin rot and ich have more visible signs in bettas, such as frayed fins or white spots on the body.
Treat your betta’s illness right away to improve its chance of recovery.
Keep your betta fish healthy by providing a high-quality diet and maintaining consistent water parameters.
#16 Death
Unfortunately, the worst-case scenario for lack of movement in your betta is death.
If you have exhausted the remedies above for an immobile betta and your fish is still not moving, it may be dying.
Look for the following signs your betta is dying:
- Lack of movement
- Lethargy
- Loss of appetite
- Color changes
- Difficulty breathing
Death may be caused by a severe illness due to poor water quality or improper water temperatures.
If your betta is more than four years old, the fish may have simply reached the end of its life.
Don’t Panic if Your Betta Fish Isn’t Moving
While a lack of movement in your betta is a major concern, it does not always mean your fish is dying.
It is normal for a healthy betta to be motionless when sleeping or resting. Slower movements are also a part of the aging process in bettas.
Frequently monitor your betta’s tank temperature and water parameters to ensure your betta stays active and healthy.
Aside from death, most causes of betta immobility are easily remedied.