Betta Fish Fights – Everything You Need To Know

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Why are betta fish also known as the Siamese fighting fish? Do they actually fight? Why?

These questions plague fish enthusiasts from all over the world, as the Betta Splenden’s aggressive reputation precedes it. These fish are known for their striking appearance and bright personalities, but often come with a warning to keep them away from other fish.

In this article, we’ll answer these questions and more. Here’s everything you need to know about betta fish fights!

Do Betta Fish Fight?

The short answer is yes – betta fish fight. Betta Splendens are colloquially known as the Siamese Fighting Fish because they are aggressive by nature. All bettas – wild or captive, are territorial to varying degrees and are likely to fight to defend their resources.

However, it is important to note that captive bettas tend to be more aggressive than their wild counterparts, as they are the product of selective breeding. Over the course of generations, captive-bred bettas have been bred for fin length, color, and willingness to fight – all of which are attributes that increased their desirability as pets. 

Today, betta fights are widely banned as they are considered cruel and unethical. Be that as it may, captive-bred bettas retain much of their aggressive streak, reinforcing the betta’s reputation as lean, mean, fighting machines.

Why Do Betta Fish Fight?

Two betta fish put inside on a separate tanks.

Simply put, male bettas fight because they are extremely territorial. A betta’s territory is important to them as it grants them access to food, mates, and shelter. The presence of another male betta poses a competitive threat. Fighting to defend these resources makes sense from an evolutionary perspective.

Both wild and captive bettas fight, but fights that take place between captive-bred fish are deadlier and more intense. In the wild, the losing male betta is able to retreat to a hiding spot to protect themselves. Unfortunately, fish tanks do not provide that option. 

Furthermore, many captive bettas have been bred and raised to be more aggressive in fights. For instance, studies have shown that raising betta fish in isolation makes aggressive behavior more likely. Many betta fish fight simply because that’s what they have been conditioned to do.

Do Female Betta Fish Fight?

Female betta fish swimming

Like their male counterparts, female betta fish engage in fights. These fights are usually motivated by the betta’s impulse to stake their claim on specific territories within a tank. Fights sometimes also break out between fish that are trying to establish a hierarchy,

Research shows similar genetic and physiological mechanisms underlying a betta’s aggression level, regardless of its gender. In other words, the selective breeding of males with a greater willingness to fight has also resulted in females who share the same tendency.

While female betta fish do fight, these fights tend to be less violent and aggressive compared to fights between male bettas. Female betta fish rarely fight to the death – they are far more likely to give up, back away, and end the fight before serious injuries occur.

Can Female Betta Fish Be Kept Together?

Because female betta fish are less aggressive than their male counterparts, many people wonder if they can be kept together for a unique aquarium display. The answer is – yes, female betta fish can be kept together, provided that you stick to a few rules of thumb:

  1. Keep them in groups containing between 3 – 5 fish. Female betta fish should not be kept in a pair, because the absence of a group dynamic may cause the more dominant fish to intimidate the other betta.
  2. Allocate at least 5 gallons of water per betta fish. Bettas are hardwired to be territorial, so providing them with adequate space is extra-important! This allows each fish to comfortably carve out a territory to call its own.
  3. Keep a close eye on your fish. Though generalizations can be made about betta fish personalities, they can vary between individuals. If there are particularly aggressive female bettas in your school, you might have to give up on the idea of housing your fish together.

Will A Male And Female Fight Each Other?

There are many differences between male and female bettas, but they can absolutely fight each other. While the likelihood of a fight happening between male and female bettas is significantly lower than the odds of a fight breaking out between two male fish, it remains a real possibility.

Therefore, we recommend that you err on the side of caution by keeping male and female bettas apart. They can be kept together temporarily for breeding purposes, but long-term cohabitation should not be in the cards. 

Will A Betta Fight Other Fish?

Most betta fights take place between members of their own species. However, bettas may on occasion fight other fish. This is especially likely if the fish in question have long, flowing fins. 

Bettas are notorious fin-nippers, and will do so almost instinctively. Therefore, colorful fish with long, flowing fins are a big no-no if you’re considering tankmates for your betta.

Pro Tip 

Bettas might also fight other fish in a community tank if there is inadequate space. Unassuming fish that encroach upon the betta’s territory risk getting attacked This creates a stressful situation for both the betta and its tankmates.You’ll need to perform 25% to 50% water changes every other week or 30% weekly if the tank is densely stocked.

Do Betta Fish Fight To Death?

Under most circumstances, betta fish do not fight to the death. The less dominant betta fish signals the end of the fight when it backs away from its opponent and disappears from its line of sight. Typically, this is what happens in the wild.

Unfortunately, this isn’t always possible. Bettas in captivity are far more likely than their wild counterparts to fight each other to the death, both because they have been genetically bred for aggression, and because a captive tank doesn’t provide space for the losing fish to hide. Sometimes, fighting to death appears to be the only option for bettas.

Although most bettas do not die as an immediate result of fights, the injuries sustained may prove to be life-threatening. Tattered fins and injured bodies are common in betta fights. This increases a fish’s risk of secondary infections from the wounds. 

Selective focus photo of blue betta fish on small glass container.

The stress from the fight also compromises the fish’s immune system, making them vulnerable to other types of illnesses and infections. For these reasons, fights are cruel. They often result in death, even if the death doesn’t immediately occur after the fights.

Signs of Fighting in Betta Fish

Sometimes, betta fights can take place sporadically for brief periods of time, leaving many hobbyists clueless to the fact that their fish are fighting. However, even if you do not manage to observe your fish fighting, there are many signs that fights are taking place in your tank.

Outward signs of fighting are obvious – your fish will bite and ram into each other. However, even if you do not observe these signs, you should keep a lookout for injuries such as missing scales and ripped fins. 

Catching these signs early allows you to separate your fish and prevent the fight from escalating.

How Does Betta Fighting Unfold?

There are several warning signs that a betta fight is about to unfold. The most immediate and apparent sign to look out for is flared gills. Bettas do this to make themselves appear larger so as to intimidate their opponents.

At this juncture, the less dominant betta fish usually retreats and hides before the fight takes place. However, this is less likely to happen in smaller tanks, which unfortunately means that the fight will progress to nipping, ramming, and biting.

How Do Betta Fish Kill Each Other?

As the betta fight escalates, the two fish will circle each other, and take turns to nip at each other’s fins and tails. This progresses until one fish either retreats, or dies. Most betta fights do not end in death, but can result in severe injuries. 

Because the costs of betta fights are high and potentially life-threatening, organized fish fights have been outlawed in the US.

How To Prevent Fighting In Your Betta Tank

The best way to prevent fights is to house one male betta fish per tank. If you have multiple betta fish, you should block them from each other’s line of sight using simple cardboard partitions, or specialized tank partitions.

Female bettas can be kept together, but you should watch your fish carefully to make sure that squabbles don’t take place. Both male and female bettas can be kept with compatible tankmates, as long as you keep a lookout for any signs of aggression.

Beautiful siamese betta fish in the glass and water at wall wooden shelf

In some cases, you might find yourself with a particularly aggressive betta fish that can’t be housed with any other fish. These fish will need to be housed alone. However, even bettas that are housed alone need mental stimulation, so be sure to place the tank in an adequately lit area of your house with lots of foot traffic!

To summarize, preventing betta fights takes diligence, but is well worth the effort. Keep a close eye on your fish, and you’ll be fine!

What Fish Make Good Tank Mates?

Most bettas are able to coexist with tank mates that have been thoughtfully selected. Most peaceful fish will make a good match as long as they don’t have bright colors and long fins. Aggressive fish, on the other hand, are a bad idea because territorial disputes may happen. 

We’ve created a list of 57 best tankmates for betta fish, but here’s a brief overview in case you needed it!

Feeder Guppies

Feeder guppies are resilient, peaceful fish that can thrive in the same water parameters as betta fish. For that reason, they make excellent potential tankmates. These fish are able to thrive without a school, making them a great option if you can have limited space in your tank.

It is important to opt for feeder guppies over the more popular fancy guppies, because feeder guppies come with nondescript colors and short fins. They are less likely to be attacked by bettas.

Pygmy Corydoras Catfish

Pygmy corydoras catfish are non-aggressive bottom feeders that come in dull colors. They also only grow up to 1 inch in length, making them a safe bet as betta tank mates.

Pygmy cories are active and will work hard to keep your substrate clean. At the same time, they will leave your bettas alone – perfect for these territorial little creatures!

Neon Tetra

At first glance, neon tetras appear to be an odd addition to this list because they are brightly colored. However, they are a noteworthy exception to the “no colorful fish” rule because they are fast swimmers that can hide in tiny crevices.

These fish like schooling, so be sure to keep at least 5 neon tetras if you intend to make this fish your betta’s tankmate.

Bonus: Snails

While not technically a fish, most snails make fantastic tankmates for betta fish due to their peaceful personalities and hardy exoskeletons. They are also fantastic algae eaters that will help with keeping your tank clean!

It is important to select snails that do not reproduce asexually, as too many tankmates will stress your betta fish out. Try to avoid snails that are too small and can fit into a betta’s mouth – bettas are curious fish and might nip at them!

How Do You Stop Your Betta Fish From Fighting Other Fish?


Thoughtfully landscaping your tank can prevent your bettas from attacking other fish. Create caves and hiding spots for each fish, so that they have a safe space to retreat to when things get stressful. 

It is also important to break up the line of sight in your tank using lots of plants and decor. This allows your betta to feel a greater sense of security over their territories, which prevents fights from occurring. Broken sight lines also provide opportunities for less dominant fish to end fights when they start to heat up. 

Tank Size 

Tank size is arguably the most important factor in keeping the peace between your betta and other fish. Bettas need a minimum of 5 gallons to feel at ease.

If you are creating a community tank, you will need a much bigger aquarium that will allow your fish to carve out separate territories to call their own. This rule is especially important if you’re creating a sorority tank consisting of multiple female bettas.

Water Parameters

Last but not least, keeping water parameters healthy can also prevent your bettas from fighting other fish. 

Bettas that are kept in less-than-ideal environments tend to be stressed out, making them more likely to attack in their agitated state. Conversely, optimum water parameters can keep your bettas calmer, happier, and much better community players.


Betta fish appear genetically hardwired to fight, but this is not always the case. Not every betta has an aggressive temperament. On the other hand, bettas with a greater willingness to fight can have these impulses controlled as long as you take the necessary precautions. 

We hope you enjoyed this article on betta fish fights! Did we miss out on anything you wanted to know? If you found this article interesting, do share it with a fellow fish enthusiast! As always, we’d love to hear from you in the comments below.

Wanda is a second-generation aquarist from the sunny tropics of Malaysia. She has been helping her father with his freshwater tanks since she was a toddler, and has fallen in love with the hobby ever since. A perpetual nomad, Wanda does her best to integrate fish-keeping with her lifestyle, and has taken care of fish in three different continents. She loves how it provides a nice break from the hustle and bustle of life.

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