Are Betta fish aggressive?

In this post, we will answer the question “Are Betta fish aggressive?”. We will also discuss the Betta fish temperament and some of the best tankmates for Betta fish.

Are Betta fish aggressive?

Yes, Betta fish are classified as aggressive fish, mainly males. Male Betta fish are often more hostile than female Betta fish, and they will establish domains that they will protect with their life if they get the opportunity. When a second male Betta fish is brought into the tank, the original male Betta will first exhibit danger signs to the new male Betta fish. In an effort to make themselves appear more significant threats and to give the other Betta fish a chance to escape before a conflict occurs, they will flare their gills and spread out their ends.

These fish can remember distances and detect dominant specimens by sight alone. This recognition mechanism helps them to prevent conflicts from ending up in fights. A physical fight between specimens entails more losses than gains, as injuries can be severe for both.

However, these exhibitions may also be performed in reaction to another motivation. During feeding periods or when guarding the Betta fish’s nest, male Betta fish may get aggressive and ready for a fight. It is also thought that Betta fish are more frightened by brighter-coloured fish, which implies that particularly brilliant male Betta fish would almost surely engage in combat with one another.

The alleged aggressiveness of the Betta fish is well known. Even people unaccustomed to the world of aquarism tend to classify the species as troublemaker and territorial.

Myth or fact?

According to experts, the Betta fish’s reputation as aggressive is somewhat exaggerated, even if the story is true. That is because it all depends on the gender of the fish. Males and females have very different behaviours and personalities.

Can male Betta fish stay together?

No. Male Betta fish are territorial and will be very aggressive if they meet another male Betta fish. Therefore, it is always recommended to keep only one male Betta fish per aquarium. This is the most effective method of preventing issues and keeping your fish safe.

Is it possible for female Betta fish to remain together? 

Female Betta fish may, in fact, remain together in the same tank. Unlike males, female Betta fish tend to be more friendly and peaceful. Thus, they can live in groups of two or more without major problems. Please ensure that your swimming companions have access to a big and pleasant area.

Betta couple in the same aquarium: is it allowed?

Yes, when the male is away from other males, he is usually a bit friendly and sympathetic. That way, a male Betta fish can stay with the female in the same space during breeding periods. However, it is important to observe the fish when introducing them, as they can get a bit aggressive towards each other.

Male bettas are susceptible to fighting and may be unable to tell the difference between a female Betta fish and an intimidation attempt. These male and female combinations have the potential to end in conflicts and perhaps fatalities. Even during breeding, the male may tease the female and resulting in her physical exhaustion or even injuries.

In general, male and female Betta fish may only be kept together temporarily when both are eager to procreate and spawn; they should be removed as soon as possible thereafter to avoid the possibility of violence between the two species.

Just remember that the reproduction of the species is usually complex and delicate. Thus, having a Betta pair in the same aquarium does not guarantee that new fish will come around.

How many Betta fish can I put in an aquarium?

This will depend on available space. The presence of two male Betta fish in the same tank is not permissible for the purpose of breeding Betta fish. Females are more friendly and easy-going with other Betta fish. However, even females need a large aquarium to live comfortably and peacefully.

When there are several Betta fish in a small space, one of them will likely become the leader of the group, showing some aggression towards the weakest ones. 

Can Betta fish live with other species?

Yes, Betta fish can get along with other fish species. As we have seen, the aggression of the Betta fish only appears when there are two males in the same aquarium or similar-looking fish.

Thus, both male and female Betta can live with other fish without major problems. However, always look for species that are compatible with the behaviour and environment of your Betta fish.

Betta fish compatible species

Several species can live with Betta fish, building a beautiful and colourful aquarium. However, always be aware of the behaviour of other species to avoid problems between your aquatic pets.

–       Neon Tetras: The small Neon tetras usually live peacefully with the Betta fish if the aquarium is large and comfortable;

–       Corydoras: They are peaceful species that usually stay at the bottom of the aquarium. As Betta fish prefer to live close to the surface, they coexist without problems. The Corys may be able to coexist with your Betta fish in an aquarium with a capacity of 20 gallons or greater. A school of seven or more pygmy cories (Corydoras pygmaeus) is usually a popular choice for Betta fish tanks; nevertheless, these fish are quite active and frequently wander up into the centre of the water column to find food. This could result in a fight between them, still, a suitably tank and number of pygmies should help reduce this aggression;

–       Snails: These animals can also live peacefully with Betta fish in a large aquarium. Snails are a great addition to any fish tank since they clean the glass and sediment, have brightly coloured shells, and add a little additional excitement to the tank. Although they may not be as electrifying as a group of bright colourful tetras, there is a reduced chance of them being attacked by your Betta fish. Nonetheless, if you have a Betta fish that is very famished and/or violent, there have been reports of snails being used as fast nibbles.

What causes Betta fish to attack and kill other fish? 

Betta fish kill one another various species by fighting them and causing open wounds on them, as well as on the water surface. These injuries can easily result in further infection and exhaustion. Betta fish fights can last for many hours, and usually result in one of the fish dying.

If you are fortunate enough to see symptoms of hostility before a full-on battle ensues, the best course of action is to separate the two fish as soon as possible. It is strongly discouraged to keep trying to place the two fish in the same tank.

What can I do to keep my Betta fish from getting into fights? 

There is no way to prevent your Betta fish from engaging in interspecies combat. Some Betta fish are far less hostile than others and might be properly housed with a diversity of aquarium companions; some individuals, on the other hand, cannot be kept with snails or shrimp without risk of harm to themselves or others.


In this post, we answered the question “Are Betta fish aggressive?”. We also discussed the Betta fish temperament and some of the best tankmates for Betta fish.

If you have any questions or concerns, please let us know in the comments section below!

Frequently Asked Questions (FAQs): Are Betta fish aggressive?

When do fish get stressed?

Fish become stressed when environmental situations are incompatible, physically exhausting, due to a high degree of competition or even dangerous situations.

How to make your Betta fish happy?

Betta fish enjoy having places for hiding and relaxing, so placing some objects in the aquarium is the secret to happiness. Find items suitable for Betta aquariums, or place items that can be sanitized, are non-toxic and do not break down in the water.

What causes Betta fish to fight? 

Betta fish typically engage in territorial disputes in order to create and preserve their region. However, they also become aggressive when protecting the bubble nest and eggs, and fries. Another reason for Betta fish fights is competition for resources, females, and shelter. 

What is the most ideal location for a Betta fish tank to be kept?

Your Betta fish must be in a quiet place with no incidence of light during the night. After all, Betta fish are not nocturnal animals. So, remember to turn off the aquarium lighting for at least 10 – 12 hours per day.

What is the best way to tell whether my Betta fish is agitated?

Betta fish will flare the operculum and also their fins. They perform this behaviour to look bigger and more threatening to other fish. 

Do Betta fish have a flaring behaviour when they are pleased?

Yes, some Betta fish can flare when they get excited by some manner of a positive stimulus, such as during feeding periods and playing time.


Why Do Betta Fish Fight? –

Sale, P. F., & Robertson, C. M. (1975). Sexual discrimination in the Siamese fighting fish (Betta splendens Regan). Behaviour, 54(1-2), 1-25.