Are Neon Tetras Aggressive?

As we all know, Neon Tetra is a peaceful fish that is not known for being aggressive.

However, in some situations, these peaceful fish can become aggressive.

But, don’t worry, in this article, we will tell you how to deal with your fish if you notice that it is becoming aggressive.

So, without further ado, let’s get started.

Do Tetra Fish Get Along? 

The answer to this question is yes, tetra fish can get along quite well.

This is because they are schooling fish, which means that they live in groups and like to be around other fish.

If you have more than one tetra fish, you will likely see them swimming together in schools.

However, it is important to note that not all tetra fish will get along.

There is always the potential for fighting and aggression among tetras.

This is especially true if you have a mix of different types of tetras in your tank.

So, if you are thinking of adding more than one tetra fish to your tank, it is important to do your research first and make sure that they are compatible.

It’s also suggested to provide them with a lot of hiding places since this will minimize aggression.

This can be done by adding rocks, caves, and other decorations to your tank.

What Causes Neon Tetra Aggression?

From our experience, if you have been experiencing regular fights between your Neon Tetras, it’s most likely due to a behavior problem rather than a health condition.

This species is not known for aggressive behaviors, and if kept in an aquarium, it is more likely to act peacefully.

However, if you are having trouble keeping your Neon Tetras from fighting, look into what might be causing the brawls to stop.

Here are some reasons why Neon Tetras might be fighting:

Resource Guarding

If fights break out when you feed your aquarium fish, or when the Neon Tetras are close to anything edible in the tank, you may be dealing with a type of resource guarding!

This occurs when one fish tries to protect its food or territory from another fish, and can often lead to fights.

To prevent this, it’s important to make sure that all of your aquarium fish have access to food by distributing it evenly throughout the tank.

Lack of Space

Neon Tetras become frustrated and irritated if there isn’t enough room for them to swim about.

If your fish are irritated, they are more likely to attack other fish and start fights, so you should think about this first if you’re seeing brawls in your tank.

Examine your fish tank to be sure it has adequate area for your Neon Tetras to swim, play, eat, and live comfortably.

If the tank is crowded, consider purchasing a new aquarium or eliminating some plants and/or other aquarium habitats.

Mating Behaviour

As we mentioned before, neon tetras are known for their friendly disposition, and they will not bother other fish unless provoked.

However, during mating, aggression may be observed.

It is not suggested to keep Neon Tetras in a community tank for this reason, as well, because their eggs would probably get eaten by other species.

Be sure to move your Neon Tetras to a different container for mating so you don’t get any instances of aggression.

You don’t want your Neon Tetras to have to be violent to survive and protect their young, and it’s usually best to put them on the road to success by keeping them away from the main tank.

Bad Water Conditions

If everything appears to be in good order, the tank size is appropriate, and your Neon Tetras have enough space to swim, you may start thinking about the water conditions.

It isn’t the most typical cause of combat, but if your Neon Tetras don’t enjoy their surroundings, they could become irritated.

On the bright side, neon tetras aren’t picky about water temperature, hardness, or anything else.

However, it is still important to keep an eye on them.

The optimum water temperature for Neon Tetras is 70°F to 81° F.

They enjoy subdued lighting, soft water (pH of 6.0 and below), and tank size of at least 10 gallons (for breeding purposes).

Aggressive Tank Mates

Some species of fish are just more aggressive than others, and it’s important to be aware of this before adding any new fish to your aquarium.

If the fish you added is aggressive, your neon tetras will become defensive and may start to fight.

Do some research on the fish you’re considering adding to your tank and make sure they are compatible with the Neon Tetras.

Illness or Injury

They can also display aggressive behavior if they have an illness or injury.

Even the most minor of injuries or sickness may cause your Neon Tetras discomfort and suffering.

A variety of illnesses are possible for a Neon Tetra, including ich, mouth tumors, and Neon Tetra disease.


The Neon Tetras are a highly energetic species.

It is easy to mistake their play for aggressiveness.

The fish are likely to engage in games with one another by chasing and leaping high into the tank.

What Are the Symptoms of Aggression Occurring?

Aggression can manifest in several different ways, making it difficult to identify and diagnose.

Some common symptoms include:

  • The fish become very active and start swimming rapidly around the aquarium
  • They may attack other fish or attempt to bite human observers
  • The fins may be erected and/or the body may be rigid

If you notice any of these signs, it is important to take action and determine the cause of the aggression.

This is necessary to provide the appropriate treatment and ensure the safety of your fish.

Without proper care, an aggressive episode can result in serious harm to both your fish and your aquarium.

How Can You Get Rid of Your Neon Tetras’ Aggressive Behavior?

There are a few things you can do to help get rid of your Neon Tetras’ aggressive behavior

Provide Them with More Space

If your Neon Tetras are acting out because they don’t have enough room, there are a few things you can try. 

First, you can increase the size of their aquarium.

Second, you can add more fish to the tank.

This will help them feel less threatened and provide them with more companionship.

Add Some Plants

You can also use floating plants in your Neon Tetra tank to give them more room and provide them with additional hiding places.

This can be accomplished by adding decorations, structures, and living plants to the aquarium.

This will allow weaker fish to swiftly find a haven from a violent encounter.

Provide Them with Enough Food

If your Neon Tetras are acting out because they’re not getting enough to eat, you can try adding more food to the tank.

This will help to reduce their aggression and ensure they’re getting the nutrition they need.

Get Rid Of the Aggressive Tank Mates

If you believe that your Neon Tetras are becoming hostile because there are other aggressive fish in the tank, you should get rid of the bad fish.

This will reduce the stress level of the neon tetra and relax them, stopping their aggressiveness.

Apply the Right Water Parameters

One of the greatest strategies to avoid stress-induced aggression is to ensure that the Neon Tetras are not experiencing too much stress.

The first thing you should do is make sure your water’s temperature is correct.

To be happy, the water must be between 72 and 78 degrees Fahrenheit.

Also, you have to keep the tank clean to minimize stress. You may accomplish this by cycling 25% of the water through it.

Separate the Sick Fish

If you have a fish in your tank that is sick, you should separate it from the other fish.

This will help to prevent the spread of the illness and keep the healthy fish safe.

Also, this will reduce the aggression behavior in your tank, because the stressed one is out now.

Ask for Help from a Professional Assistance

Persistent aggression might need professional assistance, particularly if you have already tried everything to get rid of the behavior.

Final Words

To summarize, neon tetras are not inherently aggressive, but their environment may elicit aggressive behavior in them.

When you witness them fighting with one another or bullying others, don’t be afraid; instead, figure out why they’re acting that way and take action.

We hope you enjoyed this article.

If you still have any questions, please share them with us in the comment section below.