Why Do Betta Fish Fight (And How To Stop It)

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Help my Betta Fish are fighting? Why are they so aggressive, why can’t I have more than one male in my tank (pro tip – you can with a big enough tank – more on that later). These are questions I get from my readers every week. It took me a while to approach this subject as I’ve been diving deep into the Betta fish lore.

So why do betta fish fight? There are multiple reasons, and we will go over the various today (and how to prevent this. Ready to take out your notepad? If so, let’s get started!

Key Takeaways

  • Betta fish fight for various reasons, including defending territory, breeding behaviors, stress, overcrowding, and lack of food.
  • Many betta fish breeds have been bred to fight originally, and that aggression has not gone away
  • To reduce aggression, provide enough space and hiding places in the tank for betta fish.
  • As a rule of thumb, do not place a male betta fish with another male
  • Create a peaceful environment by understanding triggers, providing ample space & hiding spots, separating male/female after breeding & maintaining good water quality.

Why Do Betta Fish Fight? (Several Reasons Why)

Betta fish, also known as Siamese fighting fish, are by nature very hostile due to a combination of their territorial nature and their history of being bred for combat. When two male bettas meet each other, they tend to display gill flaring and flaring of their fins in an attempt to intimidate.

If neither backdown, the confrontation can result in full blown battle with both trying to bite off one another’s scales or tail fin. Similarly, female betta fish can engage in fights too. Such cases do not possess the same level of aggression that males exhibit towards one another or against any type of aquatic life form. This is mainly because females have a lesser innate hostility than males do, making them less combative when compared to their counterparts.

We included a video from our YouTube channel so you can follow along. Our blog goes into more detail (and also explains how to keep multiple male bettas). Be sure to subscribe if you enjoy our content as we post new videos every week!

Territorial Behavior

The territorial instinct of betta fish can manifest itself when kept in captivity, leading to aggressive behavior towards other fish. In order to provide the necessary security for these aquatic creatures and reduce aggression, larger fish tanks should be used with plenty of plants and decorations that offer places to hide from perceived threats. Betta fish will protect their territory and bubble nest by default due to an innate survival instinct they have developed from their wild living ancestors, so giving them sufficient space is also key.

Predatory Instincts

Betta fish have an aggressive nature that is heavily linked to their predatory instincts, derived from being hunters in their natural habitat. These carnivorous creatures primarily feed on zooplankton, small crustaceans, and insect larvae, which has molded them into more dominant creatures with the capabilities to act aggressively for both securing meals and protecting against predators.

This aggression also applies to other fish who enter its space as betta’s display assertive behavior when threatened or presented with new prey, ultimately leading it to fight until one party gives up or leaves.

Breeding For Aggression

Plakat Betta Fish

Betta splendens, commonly known as betta fish, has had its fighting capabilities developed even more due to selective breeding. There were originally brought in from the wild into Asian towns by folks who worked in the rice paddies.

In the past, these fish were bred to fight, where they would be pitted against each other, and spectators would bet on the betta fish fights (similar to dog fighting). In order to condition them to fight, they were placed in tannin rich waters for a period of 2 weeks for their pre-fight conditioning. When they would fight, they would be placed back in tannin rich water to heal for another 2 weeks.

As victors became popular to breed, these more aggressive fish would create other aggressive kin as the strongest and more aggressive were favored. These fights would lead to fatalities or severe injuries. It was quite a brutal scene

These freshwater creatures were bred for their aggressive nature and found in Southeast Asia, during fights between them it could lead to fatalities or severe injuries. To this day, there is still underground Betta fish fighting occurring in Thailand. It was reported as recently as 2021 per a Vice news report1.

Fighting no longer occurs for sport legally and for good reason. However, the fighting sport has lead to more aggressive betta fish even as new domesticated breeds were forms throughout the years.

Male Aggression: Reasons and Risks

Betta Fish Interacting with Reflection

Male bettas may engage in fights due to many triggers, like striving for a mate, defending its territory and figuring out dominance hierarchy. These combats could lead to dire consequences as injury or even death of the fish involved.

Aggression can be regulated with certain precautionary measures, which include having an adequate tank size and providing hiding places along with good water quality maintenance.

Competition For Mates

Male bettas often engage in intense fights, known as ‘betta fish fight’ or ‘bettas fight’, for the purpose of establishing dominance and winning a chance to mate. Such battles can sometimes have deadly consequences but allow these male fish an opportunity to pass on their genes through reproducing during such ‘fish fights’.

To mating opportunities being at stake when betta males go head-to-head in conflict, they are also vying over resources like food that come with territory control.

Protecting Territory

Male betta fish possess an inherent desire to protect their territories from potential intruders. These incredibly territorial creatures will resort to aggressive betta fish behavior in order to guard the resources that they consider as theirs and keep control of the space around them.

In order for these confrontations or even fights between male bettas not to take place, it is essential that enough room be allocated for each individual fish so that each one has its own area which remains undisturbed by any other aquatic creature.

Consequences Of Fighting

Betta with Fin Rot

It is important to be aware of the potential risks for betta fish if they are put in a situation where fighting could occur. Not only can injuries arise from these confrontations, but also other fish watching may enhance hostility and make matters worse. To ensure that your pet remains unharmed, it is essential to understand the triggers of aggression so as to create an environment free from threat. Also, key is monitoring their behavior carefully and acting quickly should any signs manifest during conflict with another fish.

Female Battles: Causes and Prevention

Female Betta Group

When it comes to female betta fish, they are normally not as aggressive as males. Yet fights among them can still occur due to establishing a hierarchy within the group. To prevent these battles amongst your female betta fish, there must be enough space for all of them, and adequate hiding places should also be provided in their environment. Recognizing causes such as overcrowding or lack of shelter will contribute significantly towards having peaceful inhabitants inside an aquarium with multiple females living harmoniously.

Establishing Hierarchy

When female bettas are in a group (also called a betta sorority, they may fight to decide who is superior and create an order. This ranking system then keeps the peace between them afterward, although when new females enter it can cause tension as the hierarchy needs reassessing. Having said that, setting up this pecking order helps prevent potential aggression down the line.

Tips For Preventing Combat Among Females

It is important to provide female bettas with sufficient living space and places for hiding in order to prevent conflicts among them. This will help the fish feel secure, thus decreasing aggression levels. You will also get less aggression if you purchase your females that were from the same egg batch. Sisters will typically be less aggressive toward their own family. This field evidence has been documented by Betta Fish breeders such as Lisa Hudson, who runs KG Tropicals with her husband, John. She exclusively sells female bettas in Sorority batches, so you have the best chance of success.

Breeding Aggression

It can be useful to isolate male and female bettas after breeding since males have a tendency towards being hostile towards females of their species. This is because, in nature, the male will watch over the eggs in their own bubble nest. The nest is a part of their territory. Outside of breeding, males have no interest in female bettas being in their territories. If the female is not removed, there is a chance she should be injured in the process of the male trying to chase her away in a closed environment.

Signs Of Betta Fish Fighting And How to Intervene

Fighting Bettas

In order to prevent betta fish injuries and fatalities, it is essential to recognize signs of fighting. Such behavior can include flaring gills, chasing after each other or lunging, which are all telltale aggressive characteristics in these fish.

It is important that you separate them immediately if they are displaying any of these behaviors as the best way to keep a safe and peaceful environment for your pet fish. When bettas appear hostile to one another (or other fish), regularly monitoring their actions should be done. This will make sure there aren’t any issues between both sides which could lead into fights again Down the line.

Recognizing Aggressive Behavior (Warning Signs)

The escalation of betta fish is usually in stages. You can see some common signs as follows:

  • First, your Betta will flare its fins and gills to appear to look larger and intimidate their threat
  • They will then give the threatened fish a chance to leave their territory
  • If the fish that is identified as a threat does not leave, the betta will start by nipping the fins of the fish first
  • Finally, the betta will begin to circle the fish and proceed to aim for the fish’s body and attack by biting

In the wild, most fish will simply leave the territory of the betta, so conflicts do not occur commonly. However, in our enclosed environments, fights can happen, and there is no escape for the victim. Betta fish will happily fight to the death to defend their territory or will continue to fight until the intruder leaves.

Steps To Prevent

In order to avoid betta fish disputes, it is vital to separate aggressive specimens and supply them with an environment that will let the fish live in harmony. This could be accomplished by relocating the betta or the fish being attacked into isolated aquariums or introducing screens that can divide them visually.

Keep in mind, however, that the bettas, especially males, have been known to jump past the divider in order to battle the fish they see as a threat. One way to prevent this from happening is to incorporate dividers that are not clear so the fish can’t see each other. If you use separate tanks, space the tanks far enough so the two fish cannot see each other. Betta fish can and will jump if they want to fight the fish on the other side!

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Another thing to keep in mind is that we do not want to provoke your Betta fish’s aggressiveness. Decor like mirrors, which can provide entertainment for you as a fishkeeper, can actually induce stress on your fish, and they may accidentally injure themselves. These fish will also try to attack their reflection. Dark aquarium backgrounds can help prevent this behavior.

What To Do If Aggression Occurs And Injuries Are Inflicted

Injuries during fights happen. If injuries do occur with either fish (victim or assailant), you will need to separate the fish and monitor both fish carefully. Post fight recovery is important to prevent infection. Here are a few things you can do to help:

  • If your fish can tolerate softer waters, consider a tannin bath using Indian almond leaves. The therapeutic nature of these leaves is helpful for healing.
  • Use aquarium salt – 1 tablespoon of aquarium salt for every 5 gallons will help prevent infection and any stress-related illnesses. Salt will improve gill function, reduce stress, and promote disease recovery
  • Use SeaChem Neoplex – this is known as the Neosporin of the aquarium industry.
  • Use Acriflavine – commonly used in saltwater aquariums in a product called Ruby Reef Rally. This medication is used to disinfect open wounds in fish. A long bath of 3-5 days can be used or a short bath of up to two hours can be done in a bucket.

Choosing Suitable Tank Mates For Betta Fish

Black Molly

The best tank mates would be other species that aren’t too big, intimidating, and don’t look like your betta. Let’s look at a few.

Compatible Fish Species

Betta fish require compatible species in order to live harmoniously with each other. Fish that are less likely to induce aggression include:

We cover several other species in our betta tank mates posts that go into all the care requirements for them. Check it out for more insights!

Tips For Reducing Betta Fish Aggression

Betta in Planted Aquarium

In order to keep the aggression of your betta fish at bay, creating an appropriate habitat for them is vital. This should include adequate tank size with hiding spots and impeccable water quality standards in place. Let’s look into each of these factors below.

Proper Tank Size

Having an ample tank size can decrease aggression by allowing betta fish to make their own territories. For solo bettas, a minimum of 5 gallons is encouraged.

If you want to place them in a community tank, a minimum 10 gallon tank is recommended. Many aquascapes with Bettas and schooling fish will typically be built around a 20 gallon tank in the long format. Betta territories are usually 2×2 spaces, so these dimensions will clearly give your betta and your schooling fish proper space without territory disputes occurring.

Providing Hiding Spots

Creating a safe space for your betta fish is the best way to help them feel secure and decrease any possible aggression. Having several hiding spots in their environment, such as plants, caves, rocks, or driftwood, can enable them to create their own territories.

Avoiding fish that enjoy the top of the tank will also prevent conflicts. Male betta will build bubble nests, so any top dwelling fish will be seen as a threat to their nest.

Providing various refuge spaces not only gives a sense of protection to your betta, but helps avoid potential conflicts between different species too.

Maintaining Water Quality

Keeping the water quality at its best can help reduce stress and aggression in betta fish. By regularly testing ammonia, nitrite levels, pH balance and keeping temperatures on the warmer side (Bettas prefer temperatures around 78 degrees F) will provide a healthy atmosphere for them to reside in.

I Saved This For Last – How To Keep Multiple Males

Yes, it can be done! I will get plenty of hate for talking about it, but I’m an aquarist at the end of the day, not some SEO firm pretending to be passionate about this space (you know who you are😉). Let’s talk about this controversial subject and how to pull it off.

I present to you documented field results by my fellow YouTuber Aussie Aquatics. In the video below, he discusses his 2 year journey of keeping two male betta fish in the same tank. This video below is his part two update. Here are a few insights he provides

  • Males will typically defend a 2 foot long space
  • The purpose of flaring is to chase other fish away from the territory – they don’t want to fight
  • The size and length of a fish tank determines how many male betta fish you can keep
  • His tank is 3 feet long and 135 liters (approx 35 US Gallons)
  • There will still be one dominant male, but the two will tolerate each other and the passive male will yield to the dominant one
  • Breeding farms in Asia will have hundreds of betta fish together in community groups in ponds
  • The minimum length for 2 male bettas to live in the same tank is 3 feet long
  • A heavily planted tank is a must for this to succeed, as this gives plenty of hiding spaces for both fish

The long awaited video is below:

There are more and more hobbyists in the pet fish trade reporting success on this once taboo subject. It’s very possible to keep more than one male betta if you have a large enough tank!

Frequently Asked Questions

How do I stop my betta fish from fighting?

To stop your betta fish from fighting, keep only one male per tank and provide a visual barrier between the tanks so they can’t see each other. A dark divider will work as an effective barrier.

Should I let my betta fish fight?

It is imperative to remember that betta fish are alive and must be treated with tenderness and reverence. It’s not just inhumane, but it can also result in serious health conditions for the fish if they are allowed to fight each other. Betta fish should never partake in such activity as it could lead them to injury, infection, and even death. One must ensure that no harm comes upon these delicate creatures through fighting.

How do I stop my betta fish from fighting?

To stop your betta fish from fighting, keep only one male per tank and provide a visual barrier between the tanks so they can’t see each other. A dark divider will work as an effective barrier.

Why are my betta fish attacking each other?

The fighting behavior amongst your betta fish might be caused by them trying to establish their own territories and resources, which is something that occurs in many species of freshwater fish. To tackle this issue, it’s important to recognize what the underlying cause is – whether a natural behavior or due to how they were raised. Providing adequate space for each one and necessary supplies should help with any territorial issues among them.

How long do betta fighting fish last?

The typical betta fish lasts only a few minutes or can end immediately. In an enclosed environment, it’s very possible for these fish to fight to the death as the losing fish needs to escape the fought over territory for the fighting to stop.

Why are betta fish so aggressive?

Betta fish have long been associated with aggression due to their territorial nature and predatory leanings. This has led to the popular practice of selective breeding, aimed at developing increased combat capabilities in these aquatic creatures. As a result, betta fish now possess more aggressive tendencies, which make them even better suited for fights. It is this enhanced aggressiveness that gives rise to an overall boost in their popularity, as the flaring display is considered attractive looking by some hobbyists.

Closing Thoughts

In summary, the causes of aggression in betta fish are multifaceted and based on their natural behaviors such as being territorial, hunting habits, and selective breeding. To maintain harmony among your pet fish, we suggest that you understand why fights happen between them. Also learning more about these vibrant animals can be helpful when trying to promote a safe space for both tank mates and betta fish alike.

Whether you have long been enamored with this species or are simply getting started, this article gives an insight into making sure all parties within the aquarium enjoy peace. Did anything in this article surprise you? Leave me a comment in the comments below, and let’s talk about it. Until next time!

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