Gouramis are beautiful freshwater fish that are a much-loved fish for many home aquariums. They come in various sizes ranging from dwarf to large, and there are many great varieties to choose from. Gouramis are pretty easy to care for and generally get on well with other fishes. However, because they tend to become aggressive when not placed in the right aquatic environment, they are often rejected by new owners. In this article, we explore which gouramis are most aggressive, potential reasons why, as well as the warning signs to look out for in your tank.
Are Gouramis Aggressive?
Although Gouramis are not aggressive fish, males can become very aggressive towards each other when they feel threatened, nipping fins and generally bothering other fish in the tank. Wherever possible, we recommend keeping male Gouramis individually.
Female Gouramis, on the other hand, are more peaceful than males. They are only aggressive if they feel threatened by a fish that looks similar in shape and size.
Do Gouramis Fight Each Other?
Gouramis are typically peaceful fish. However, male gouramis can be highly protective. They will occasionally fight over a female, particularly when there are more male Gouramis in the tank than females.
What Causes Aggression In Gouramis?
It’s no surprise that Gouramis fight over a lot of similar things that other species do; food, mates, and territory. Let’s take an in-depth look below:
Territory
The majority of aggression in the tank is regarding territory. Most fish swim around the tank without a care in the world, but Gouramis can be incredibly protective over the area of the tank they call home. Their environment provides a safe space to sleep, hide, mate, and spawn. The area they mark as their own could be something simple as a large plant or rock. Whatever area they choose, Gouramis will allow certain fish to enter and become aggressive to others that come too close.
Similar Fish
Gouramis are most territorial towards other Gouramis and are particularly aggressive towards Gouramis of the same sex. To put it simply, if a fish looks similar and is of the same sex, a Gourami may see this as a threat and will become aggressive towards the other fish, often chasing after it or nipping its fins.
Fighting For Food And Mates
Aside from fights about territory, aggression in Gouramis is triggered by a battle for food and mates. Female Gouramis are highly defensive and aggressive when it comes to protecting their eggs or fry, whereas male Gouramis are most aggressive when mating.
What Are The Signs Of Aggression Occurring?
Not all signs of aggression in Gouramis are noticeable. The majority of the time, fights amongst fish occur when you’re not looking. It’s not that Gouramis are waiting for you to turn away, but rather the majority of attacks happen overnight. Below we’ve listed five things to look out for in your Gouramis behavior, as well as noticeable signs of aggression in your tank:
Chasing Other Fish
This behavior is one of the easiest to spot. One Gourami will chase after another fish and likely headbutt them or bite them. Sometimes the threat of the encounter can make the other fish in your tank hide for long periods.
(If you already have gouramis, here are all the best tank mates you can keep with gouramis, as well as how to care for them!)
Feeding
A lot of the competition in an aquarium is over space, breeding, or food. Typically, aggressive gouramis will swim around quickly, eating as much food as they can, even stealing it out of the mouths of other fish. To reduce food competition, you ideally want to feed your fish various floating and sinking foods, allowing them to spread around your tank and provide all your fish with ease.
Breeding
Female Gouramis are extremely protective over their unborn young, becoming aggressive if they feel there is a threat. Expectant Gouramis will attack other fish they feel are coming too close in a bid to give them more space. They have even been known to nip at human hands that come too close to their nest!
Noticeable Marks Or Injuries
Do any fish have broken or split fins? A rotten tail causes jagged edges on fins, but split fins are due to a physical injury from fighting. Have you noticed your fish hiding behind rocks and driftwood more? It could be scared of a more aggressive fish in the tank. Other signs to look out for are your fish changing territories in the tank, as well as scratches and scrapes on their gills and injuries to their eyes.
Illness
Aggression in Gouramis can sometimes be a sign of an illness either in themselves or of another fish. Either way, when a fish is aggressive, you should continue to watch them to try and identify if there could be an underlying cause.

How Can You Stop Gourami Fish From Acting Aggressive?
If you notice aggressive behaviour in your tank, your first instinct will be to intervene by removing the aggressive fish. While this offers a great temporary solution, there are many other things you can do first.
Let Them Fight
Sometimes, fish need to understand their rank in your aquarium in order for them to calm down. That means letting them fight. While it can be upsetting to see some of your fish distressed, fish normally calm down within a couple of days once they’ve had the chance to assert their dominance in the tank.
Add Decorations And Plants
Some Gouramis are too docile and are easily bullied by aggressive fish. An easy way to stop this is to add plenty of decorations and plants to your home aquarium so your less aggressive fish can hide from their bullies. Rocks, driftwood, and caves all provide fantastic hiding spaces for your fish, helping to spread out aggression. You can also add tall plants or plants with thick stems to help create a safe space for your fish and reduce visibility in the tank. Incorporating these pieces into your home aquarium doesn’t just help provide territories for your fish; it helps improve the look of your tank too!
Add A Larger, More Aggressive Fish
While this doesn’t always work, you can try adding in a larger, more aggressive fish to your tank. Aggressive fish will often exert their dominance in a bid to show other fish who’s the boss. They are highly aggressive to other fish that threaten them. By adding in another more aggressive fish, it can change the tank dynamic completely, resulting in a more calm atmosphere.
Use A Tank Divider
If you’ve followed the steps above and your fish are still aggressive, the only other choice you have is to separate the fish. A simple and effective way of doing this is by using a tank divider. A tank divider slots into your tank, allowing you to conveniently give your fish time away from each other.
(Find out about the 13 different types of Gourami.)

FAQ
Are Kissing Gouramis Aggressive?
Kissing Gouramis get along with themselves and many other fish. However, if a male and female break off to mate and spawn, they will get aggressive protecting their eggs and fry. In this instance, you can use a tank divider to separate until their eggs have spawned.
Are Dwarf Gouramis Aggresssive?
Dwarf Gouramis are extremely docile fish and make an excellent addition to any home aquarium as they thrive in environments with members of their own species as well as other peaceful small fish. As they are small, they are sometimes bullied by larger fish, so it’s always worth consulting an aquarium professional before putting them into a tank with a lot of other species.
Are Pearl Gouramis Aggressive?
Pearl Gouramis have a highly calm temperament that often does not bother other tank mates. Male Pearl Gouramis can become extremely aggressive when competing for a mate, whereas female Pearl Gouramis will show signs of aggression when protecting her eggs.
Can Gouramis Kill Each Other?
While Gouramis are largely peaceful fish, aggression amongst males can sometimes lead to them killing one another. Although this is rare, it has happened when there has been more than one male in the tank. As male Gouramis try to assert dominance over one another in the tank, they can get into nasty fights, biting fins and, in some instances, killing each other. What starts as intimidation can quickly turn nasty, so it’s important you monitor your fish regularly. If you are noticing this problem frequently, you may need to upgrade the size of your tank – the less space in your tank, the less chance your fish will have to mark their territories.

Conclusion
Ultimately, Gouramis are mostly peaceful fish. While they can show signs of natural aggression, so can many other species of fish. That said, it’s not a reason to avoid Gouramis, as many of them have a calm temperament, are highly intelligent and stunning fish that, most of the time, add a lot to your home aquarium. If you are unsure about purchasing a Gourami for your aquarium, or your Gourami is acting aggressive, and you’ve tried all our steps above, it’s important to always consult an expert.