Betta Fish Fighting – Why do Betta Fish Fight?

The other name for Betta fish is Siamese Fighters fish and that name accurately describes the main feature of their character. 

These fish are fearless and gracious, and literally always ready to fight. Even the name Betta is from the ancient warrior clan “Bettah”.  

Male betta fish are way more popular than females thanks to aggressiveness. Males are also prettier and do become even prettier when they are excited and ready to fight. Their otherwise vivid color gets an even stronger glow then and takes on a fascinating, and little bit mystical look. 

History of Betta Fish Fights

There are many lovers of these beautiful creatures all over the world, however many who keep them as pets do not understand why they are so aggressive. For those uninformed or less careful owners of betta fish – challenging Betta to fight can be interesting and fun, and they are often upset or exploited.

Betta fish are very easily triggered to fight and that is the number one reason for their mortality. They are fearless in combat and often attack for no apparent reason. Aggression is an important part of their evolutionary development. Betta fish are native to the tropics and to survive and fight for space and food they had to be ruthless. It is part of their primal instinct. 

However, Betas won’t hesitate to attack fish of a brighter color or fish with bigger fins, or just anything that gets in their way.

In the 19th century, there was an official sport in Thailand that involved the gladiatorial fight of Betta fish. It was massively popular that the King of Siam had to regulate it through taxes and laws. Over time, through artificial breeding and inadequate conditions, aggressiveness, as the basic character trait of Betta fish, came to the fore.

Why Are They Fighting?

Before they became globally popular as beautiful and exotic pets, betta fish were bred for the so-called. Fish fights. For that reason, researchers cannot determine whether extreme aggression is caused by artificial breeding of Betta fish, poor breeding conditions or it is a common feature of both wild and farmed Betta fish.

What is certain is that they are all aggressive, but not always and not with equal ferocity. As with almost all animal and fish species – the reason for the fight is the fight for territory, food and females. That is why it is impossible to keep two males together in an aquarium, as well as male Betta fish with other species. Sooner or later – it will become bloody. 

Some irresponsible owners enjoy watching situations like this, so they do it on purpose. They are especially interesting because the body of a Betta fish then takes on stronger colors and almost shines.

It is important to note, however, that such behavior is not moral or consistent with animal welfare concerns.

Are All Betta Fish Aggressive?

Many owners and fans of betta fish testify that not all of them are equally aggressive. It is possible that the calmer betta fish came from a better quality farm, where they had enough space, water and food, so there was no need to fight.

If you are planning to enrich your aquarium with Betta fish – it is important to know that it is a risky endeavor. However, there are a few tactics that can work. 

Are Betta Fish Aggressive

Do not put Betta fish in an aquarium with equally aggressive species and never in a very small aquarium. First, let the other types of fish get used to each other, and add the last betta fish and watch. If Betta reacts immediately violently, it is best to place her in a special aquarium.

If you really want a betta fish – you can take a female. They are less aggressive and easier to adapt with other species. But you also have to be careful with the female. They are territory-oriented and once, with a lot of noise and battle, they establish a hierarchy in the aquarium – each new inhabitant – will provoke an aggressive reaction.

Females are also less attractive, but perhaps a great way to get acquainted with this specific and demanding fish species.

Signs of Hail on Betta Fish

You will recognize the fight by betting fish into each other or squeezing. In principle, fish are fighting for territory, and this is best seen in betta fish that live in the wild. If there is enough territory and food here and two males meet by chance – most likely everything will end in intimidation. 

That is, it will spread its lush feathers, and the weaker fish will take shelter. Some will only provoke by nibbling and pushing and the weaker one will, if he estimates that there is no chance, take shelter. If, on the other hand, the space inhabited by two males is small and food is limited – the fight will be relentless and last until death. Such fights, depending on the strength of aggression and anger, last from a few seconds to a few minutes.

In aquarium conditions, especially if the aquarium is small and cluttered with sand and walls – the fight can be relentless without ending in death immediately. Betta fish will be injured, torn feathers and shells. She will be scared, avoid food and eventually die. Betta fish that are specially bred for fighting can fight longer and bloodier. It is generally believed that purpose-bred bettes are intentionally kept in a small space to increase aggression and easier provocation to fight.

Betta fish males will also fight to defend the bubble fish nest. Nest building is most often a sign of imminent mating, although males often do so beyond the mating season.

It is specific that in this fish species the males are the ones who take care of the offspring, i.e. until they hatch and the female needs to be transferred to another aquarium immediately after spawning, otherwise she could eat eggs and the male mostly kills her.

Is There a Way to Prevent Betta Fish Fights?

Aggression is in their nature and while in the wild it is less pronounced – farmed betta fish are almost impossible to prevent from fighting. If you put a mirror in the aquarium, they would attack their reflection. They also attack anything or any other type of fish that reminds them of a Betta fish. 

In general, many decorations and accessories for aquariums are popular, but even that can be a combat trigger for Bettas. That way he can get hurt by attacking an imaginary enemy. Also, extra small fish tanks or lack of space will raise their anger.

The safest way to avoid fights is to keep the betta fish alone in a separate aquarium with little decorations and some plants. If it is a large aquarium, you can try to make separators or buy them in a pet store. Some researchers have tried treatments based on marijuana and Prozac, but it is still safer to think carefully before buying a Betta fish, whether its character suits you and whether you are ready to create special conditions for them.

Fighting Males and Females

Betta fish love lasts very short. Just during mating seduction and the act of love. As soon as the female releases all the eggs, aggression occurs. Either she will eat the eggs that fall out of the nest or she will be killed by a male, or both. 

Males and Females

Even outside the mating season – males and females will attack each other, in the same way that males do

The reason is mostly territory and food. Females in sorority establish a very strong hierarchy among themselves, which, if not disturbed by the new occupant of the aquarium, can live a long and peaceful life without major complications. However, the mixed community of males and females in the Betta fish in the aquarium has no chance of surviving.


If you are bothered by the aggressiveness of the Betta fish, and still want it as a pet – the simplest way is to provide it with a separate and large enough aquarium. Do not overload it with additives or herbs. In addition to regular feeding and maintenance of the aquarium, your fighting friend – will be happy and will live long.

If you do the opposite and put the Betta fish in the aquarium with other species – there will inevitably be bloody fights. Betta fish are small creatures, and big warriors and winners. 

Thanks to their inviolable fighting spirit – the survivors still make the whole world happy today.