Do betta fish attack other fish?

In this blog we will discuss betta fish attacking behavior.We will also discuss the reasons for their aggression and thet type of tank mates which triggers aggression in them.


In this blog

  • Do betta fish attack other fish?
  • What are the main reasons for betta fish aggression?
  • Common signs of aggression in betta fish
  • List of fish that gets attacked by male bettas
  • Do overcrowded tanks trigger aggression in bettas?
  • What are the best companions for bettas?
  • How to make bettas less aggressive?
  • Summary
  • Frequently asked questions
  • Reference

Do betta fish attack other fish?

Betta fish or siamese fighting fish are very territorial and have the potential to fight other fish that share an aquarium.

Male betta fish especially like to bite fins and attack other fish and they only end the fight when one of the fish dies. Most betta fish won’t go near this point, but the fight is cruel.

Bettas are very aggressive and males often fight each other until they die. Even female bettas can be aggressive, but usually more sociable than male bettas. In the community tank, betta attacks other flashy species, but works well with lighter-colored species.

What are the main reasons for betta fish aggression?

Betta fish fight for territory,including food resources, shelter, and access to females.Their aggressiveness is due to a neurotransmitter called serotonin.Low levels of serotonin are the main reasons for their aggressive and territorial behavior.

Aggression is more in male betta fish than female bettas.The female bettas can co-exist in community aquariums too.This species evolved aggression in male bettas because of their breeding behavior.

Male betta fish are known to guard their bubble nest and eggs by not letting any aquarium species come closer to their fertilized eggs.They tend to attack anything that tries to come near their eggs by flaring their fins and other aggressive behavior.

Common signs of aggression in betta fish

  • Gill flaring
  • Ramming
  • Fin nipping 
  • Missing scales
  • Torn fins
  • Increased hiding or prolonged hiding periods
  • Lethargy
  • Decreased appetite
  • Sudden death

List of fish that gets attacked by male bettas

Other male bettas

Males equip the territory around plants or stones. They become very possessive of their territory. The fighting fish fight to defend its territory from intruders. They will fight until the enemy is injured or retreats.

Male Bettas cannot be kept with other species in similar aquariums because of their fin biting behavior. And if they are kept with other male bettas then, they get aggressive and fight each other to death. 

Their fights can last up to some 15 minutes and could be nasty and can possibly stress out other male bettas and out of stress,infection and trauma it can kill the opponent.


Mollies are less aggressive than male bettas but they attack each other in order to build their hierarchy.Male bettas have beautiful long flowing fins,which are very attractive and mollies are known for their fin nipping behavior.

So it’s very much possible that bettas fin will get nipped by mollies and in turn this will cause aggression in bettas leading to fight and attack on mollies.It’s better to keep them separately.Fin-nippers should not be kept with male bettas at any cost. 


Male guppies are brightly colored with flowing tails. Both cause males to be aggressive and territorial. Pairing a male guppy and a male betta together will cause problems and most likely lead to the death of your guppies. 


Bettas are known to be aggressive, while goldfish are fin nippers. If you put your betta in a tank with goldfish, chances are it will end up clipping off its fins. 


The blue gouramis also known as three-pointed or opal gouramis, grows larger and is known for chasing and biting betta fish and even killing them.This is due to the naturally highly aggressive nature of both species.

It is not recommended to mix betta and gourami fish because they will fight to establish their hierarchy, causing stress or the fish attacking each other.A Betta will do well with some dwarf species of gouramis but some of the larger species may be territorial.

White cloud mountain minnows

Bettas are very particular about their space in their tanks and won’t like it if the other tank mates are invading their spaces.

Bettas and white cloud minnows occupy the same levels in the tank and this will trigger their aggression and bettas will end up attacking peaceful minnows.It would be better to not keep them together in a similar tank.

African dwarf frogs

The real problem is that African frogs eat incredibly slowly and it is not uncommon for African dwarfs to become hungry when there are other fish like bettas,who are known as voracious eaters in the same aquarium.

African frogs are known for nipping long flowing fins and this might trigger aggression in male bettas.


It’s not a good idea to keep a betta with any type of cichlid, even in a large aquarium. Cichlids will harass and eventually kill male bettas. 

They bite their large flowing and wavy fins, causing injury and eventually death from infection. Large cichlids are known to swallow a whole betta. 

Ghost shrimps

In addition to plants,ghost shrimps can also eat meaty food. So whatever your male betta doesn’t eat, the ghost shrimp will. 

Sometimes you may even notice that the ghost shrimp will swim up to the top of the aquarium to eat the betta food.This will trigger aggression in male bettas and they end up killing or gobbling up ghost shrimps.

Why are fin-nippers not good for bettas?

If your betta is bitten or nipped by fin-nippers, not only may your betta start attacking other fish in the aquarium, but they may also get stressed and have an increased chance of developing fin rot.

Bettas’ long flowing fins are so attractive,that fin nippers don’t leave a chance to nip them off.It is very important to never keep your bettas with fin-nippers as they trigger aggression and cause fin rot in bettas.

How to stop betta fish from fighting or attacking other fish?

The best way to stop male betta fish from fighting is to keep only one male per aquarium.When keeping male bettas in separate tanks, install a visual barrier between the two aquariums so that the bettas cannot see each other at all times. A simple aquarium background or cardboard piece are effective visual barriers.

Toys with mirrors and mirrors located near the tank should also be removed as male bettas are known to react to their own reflections.These can cause stress in male bettas and are one of the reasons for aggression in them,and bettas might end up hurting themselves by chasing their own reflections.

If the tank is too crowded, male bettas are likely to act aggressively towards other species in the same tank,because they don’t have enough space for their territory. If you plan to keep your betta with other fish, make sure you have enough space.

Do overcrowded tanks trigger aggression in bettas?

Bettas like large and spacious tanks,the minimum tank size to house a single betta is 5 gallons and housing them in groups requires bigger and more spacious tanks.

If they are kept in community tanks,they might be needing bigger tanks for their proper growth,swimming and hiding.If they don’t get proper space they will show aggression and fight with other tank mates for space.

Bettas are very much particular about their space in the tank,sharing their space is not possible for them.

What are the best companions for bettas?

  • Celestial pearl danio
  • Cardinal tetra
  • Black neon tetra
  • Diamond tetra
  • Corydoras 

How to make bettas less aggressive?

Bettas tend to be less aggressive if they have enough space to develop their territory. More space will also prevent other fish from continuing to swim in the area once established. More space also gives these fish the space they need to retreat if a betta fight begins.


They are named as fighting fish for the male-to-male aggressiveness. While individual betta fish behavior may vary, most male bettas in the pet fish trade need to be kept in separate aquariums without even seeing other males. 

Fighting betta fish can be deadly, so owners need to take effective measures to prevent male betta fish from fighting.

Fish that resemble a male betta fish are considered a threat and get attacked.Avoid keeping flashy or brightly coloured fish and long decorative fins with male bettas especially,as this triggers aggression in them.

Bettas personalities vary greatly from individual to individual.Some may be okay with a few tank mates,while others attack and kill for no apparent reason and continue to do so.These bettas and especially male bettas are best kept alone.

It’s also important to add bettas to the already established tanks, because bettas in their aquarium established their territory and consider other new species as a threat.

Frequently asked questions

Can we keep male bettas with tank mates?

Male bettas are not meant to keep with other male bettas,female bettas and other species because of their aggressive nature.It’s better to keep them in a solitary tank to avoid such attacking behavior. 

Can female bettas live in community tanks?

Female bettas are less aggressive than male bettas and can get along well with other female bettas and other tank mates in community tanks too.They only get aggressive if a male betta is introduced in their tanks for mating.

But it is not advised to keep female bettas with male bettas other than mating period.They should be separated after breeding without fail.

Which is the most aggressive type of betta?

Plakats are also the most aggressive type of betta,and only the most aggressive one is selected for breeding purposes and these plakats are small fish with lots of aggression in them.

They also have a bad habit of leaping out of their aquariums, so you definitely need an aquarium with a tight hood, without gaps.