Why is my betta fish stressed?

In this post, we will answer the question “Why is my betta fish stressed?”. We will also discuss the different reasons, types of stress and symptoms.  

Why is my betta fish stressed?

There are several reasons for your betta fish to be stressed, the most common ones are lack of space, overpopulated tank, inappropriate conditions, lack of resting or hiding structures, aggressive tankmates, and abrupt changes in conditions.

What is stress?

Stress in fish is quite comparable to stress in people, according to research. The situation in which your betta releases cortisol and adrenaline into your betta’s system is known as the stress response.

Low/Long term stress

Low or long-term stress is stress that is modest in intensity, yet happens regularly. In a low-stress, long-term stress situation, your betta will be continually attempting to adjust to the new surroundings. This will harm its immune system and health, which will gradually worsen. If a betta is pressured for an extended period, it will exhaust itself and eventually die.

High/Short term stress

High short-term stress is another sort of stress to be aware of. There will be a significant amount of tension that occurs very quickly, but it will not be continual. The consequences of significant short-term stress will only linger for a few days at the most, if at all. However, repeated exposure to this form of stress is still detrimental to your betta’s health and wellbeing.

Reasons for stress in betta fish

Stress may be caused by a variety of different factors in betta fish. One of the most important things you can do to keep your betta happy and healthy is to be able to identify the problems and manage them appropriately.

Lack of space

When choosing a container for your betta, you should never choose a container that is less than 5 gallons in size. When a tank is less than 5 gallons, it will become filthy very fast, causing your betta to feel stressed and unhappy.

Overpopulated tank

Just like with a tank that is too tiny, an overly populated tank can create circumstances that are too poor for your betta to live. It is recommended that you add one inch of fish per gallon of water if you are unsure of how many fish to keep in a tank. 

Nonetheless, you should treat the guideline with a grain of salt and properly investigate the ideal tank size for any species you intend to keep with your betta.

Inappropriate conditions

Even if your tank isn’t congested and is sufficiently sized, the circumstances may still be unsuitable for your fish. You should also check to see that the pH of the tank is correct, as well as that the temperature is within acceptable limits. Bettas in cups are sometimes seen at pet stores, but this is not the proper way to care for them, and if they are kept in these conditions, they will die rapidly.

Making certain that the tank’s conditions are optimal is not only crucial for your betta but is also essential for any other living species in the tank. In addition, if the circumstances are not favourable, a rise in hazardous bacteria, parasites, and algae is likely to occur.

Lack of resting and hiding spots

You should provide your betta with several hiding spots where it may relax because it is a lonely creature. You should expect your betta to get increasingly stressed if it does not have any downtime and always feels on edge, as described above. As a result, it is vitally necessary to decorate your tank in a way that it feels secure.

Tankmates aggression

Aggressive tankmates that bully your betta are going to be short/high-stress sources for your betta, but if they are allowed unchecked for an extended period, they can bring long-term stress. The possibility that another fish in your aquarium may bully your betta is unlikely, yet it does happen. 

Unfortunately, because bettas are not quick swimmers, fish that are fin nippers may take a nibble before sprinting away from the aquarium. The stress this causes your betta will not only make it sick but will also raise its chances of contracting fin rot, which can be deadly if not treated promptly. 

The difficulty in dealing with aggressive tank mates is that there is no way to get away from them. When a fish behaves aggressively in the wild, your betta has the option of either swimming away or fighting the fish. Swimming is impossible in a tank since there is nowhere for it to go.

Abrupt changes in water conditions

You should also be on the lookout for unexpected changes in the water’s temperature and clarity. The stress caused by slowly deteriorating water is little, but when the water moves suddenly, it can frequently shock your betta or stress it to the point of death. 

The water conditions in your tank can alter as a result of a variety of factors. Perhaps you brought anything into the aquarium on purpose (such as a new decoration) or by mistake (such as a new filter) (accidentally spraying chemicals into the water). Whatever the case may be, you’ll need to move fast to resolve the matter. 

Additionally, sometimes it is out of your hands totally and you have no influence over what is happening. A heater failure, for example, might result in an abrupt change in the water’s conditions.

What are betta fish stress symptoms?

Stress in bettas manifests itself in a variety of ways, some of which may be considered normal behaviour. You should get to know your betta and its quirks so that you can recognise when anything is causing it to get stressed. The following are the most often seen signs of stress in betta fish.

It seems off

One of the first indicators of a worried betta is that they appear to be acting a little strange. It’s possible that they aren’t swimming as much as they used to. Or their personalities may be different. Whatever the case may be, it will never be the same again. 

Detecting this early on is one of the most effective strategies to eliminate the source of stress before it becomes more severe.

Lack of appetite

Another symptom is a lack of desire to eat. When your betta’s hunger disappears, you realise there’s a problem with its health. They have a strong will to survive, and it takes a lot to scare them away from their meal. 

However, don’t interpret a lack of appetite as an indication that they are suffering from stress alone. It can indicate a variety of conditions, including that your betta is ill, constipated, or even depressed in certain cases. 

If you’re trying to figure out what’s wrong with your betta, a lack of appetite should be one of the symptoms you look for.

More prone to diseases

If your betta has grown ill, it is most likely because of the stress it is experiencing. Many people believe that sickness is the source of stress, while in fact, it is stress that causes disease. Stress will impair the immune system of your betta, leaving them more susceptible to infection.

Altered swimming behaviour

It is typical for your betta to dash around the tank every once in a while, and this is very acceptable. However, if you find your betta continually darting about or engaging in any other jittery swimming activity, you should investigate the source of the problem immediately. 

This is very certainly because it is fearful of its tank mates, but it might be due to anything else in the tank or outside the tank.


Another symptom of stress is that it is difficult to detect. It’s very normal for your betta to go into hiding now and again. If, on the other hand, you see that it is spending the majority of its time hiding rather than swimming, there is something amiss. 

It is necessary to determine whether the fact it is concealing is due to bullying or is being concealed due to some harm it perceives.

Change in colour

A change in the colour of your betta’s skin may also be noticeable. As opposed to being its typical brilliant and colourful self, your betta may begin to grow duller and less vibrant over time. 

When it’s swimming about, it’ll appear a lot paler and won’t capture your attention quite as much. In addition to this, you may detect stripes of a different hue running over the skin of the creature. These are referred to as “stress stripes” in the industry. 

Your betta’s colouration may fade if it’s sad or, in uncommon instances, if it has a hole in its skull.


In this post, we answered the question “Why is my betta fish stressed?”. We also discussed the different reasons, types of stress, and symptoms.  

If you have any thoughts or doubts, feel free to drop us a comment below!

Frequently Asked Questions (FAQs): Why is my betta fish stressed?

What can you do to assist a worried betta fish? 

Make use of water conditioners such as API Stress Coat Aquarium Water Conditioner, which is developed to minimise fish stress by 40 per cent by the removal of toxic wastes from the aquarium. Alternatively, API Stress Zyme Aquarium Water Conditioner helps to keep your aquarium cleaner while also aiding in the stimulation of its natural cycle. 

What is the best way to detect whether a betta fish is stressed? 

Swimming in an Odd Place: When fish are under stress, they frequently exhibit unusual swimming patterns. If your fish is swimming wildly without making any progress, falling to the bottom of its tank, rubbing itself against gravel or rocks, or locking its fins at its side, it may be suffering from severe stress and should be sent to the veterinarian immediately. 

What is causing my betta’s dissatisfaction? 

When the betta is unwell, it may exhibit depressed behaviour. If your betta is sluggish, check the temperature of the tank and the water quality. You may need to perform a water change or turn up the heating.

Is my betta fish in a stressful or joyful state? 

A betta who is content will swim around its tank regularly. They may wander almost slowly across the room at times, and they can also flutter from side to side fast at other times. A healthy and happy betta does not appear to be having any difficulty swimming and is not leaning to one side or straining in any way. 

What are the signs that my betta is depressed? 

When your betta is sad, you’ll notice that its vitality has diminished and that it has become dull. In addition, you may begin to observe stress stripes on its side, and the colour of its skin may not appear to be as vibrant as it once did. These stripes can also be created by tension, which is why they are sometimes referred to as “stress stripes.” 

Whats is the normal betta fish behaviour? 

Betta fish are lively, joyful little fish that aren’t shy about displaying their happiness to others. Betta fish will aggressively consume food without any difficulty and will swim up to you if they believe you might be interested in a snack. When it comes to personality, these beautiful fish may be highly expressive, so don’t expect anything less when you own one.


Stressed Betta Fish – https://www.bettacarefishguide.com/stressed-betta-fish-guide/

Stress in Fish: Symptoms and Solutions. https://www.hartz.com/stress-in-fish-symptoms-and-solutions/

Young, T., & Bone, J. (2021). A better life for betta fish. Every Child, 27(2), 8-10.