Hepper is reader-supported. When you buy via links on our site, we may earn an affiliate commission at no cost to you. Learn more.

How To Stop Cichlid Bullying & Aggression- 9 Easy Steps to Follow

Lindsey Stanton Profile Picture

By Lindsey Stanton

two male cichlids fighting

Cichlids are some of the most beautiful fish that you could have in an aquarium. However, they are also known to be quite aggressive, both towards each other and other fish species. Simply put, cichlids can be bullies.

starfish divider ah

The 3 Reasons Why Your Cichlids Are Attacking Each Other

There are several reasons why your cichlids may be attacking each other and other fish. Let’s do a quick rundown of the various reasons why cichlids behave in this manner.

There are three main ones to consider.

1. Reproduction

Cichlids are by nature quite competitive and aggressive, with one of the main reasons for this being the competitive drive to reproduce.

Male cichlids can be especially aggressive towards each other during mating season as they compete for the right to mate with a female cichlid.

This issue becomes clear when you have many cichlids of the same species in the same tank, as cichlids of the same species will be especially competitive with each other.

a pair of Bolivian ram cichlids in the aquarium
Image Credit: DMITRII STARTCEV, Shutterstock

2. Food

The other main reason why cichlids are so aggressive towards each other is also due to their competitive nature, but here we are talking about food instead of women.

If you think about it, it’s really no different from the human world, and the rest of the animal kingdom in general with males competing for each other for food and women.

Food and the need to reproduce are always the two main things that cause competition in the animal kingdom.

3. Territorial

The third reason why cichlids might attack each other is due to territoriality. Simply put, a cichlid may see this part of the aquarium as his or her own, and they will protect it at virtually any cost.

If you don’t have a lot of caves, rocks, and natural barriers in a tank with many cichlids, they will become overly aggressive to compete for control of what they see as their territory.

Blood Red Parrot Cichlids in tank
Image Credit: Arunee-Rodloy, Shutterstock

wave tropical divider

The 9 Ways to Stop Your Cichlid From Being Aggressive

There are several things that you can do in or to your fish tank that will help curb cichlid aggression. Any one of the following actions on their own may not be enough to totally eliminate cichlid aggression.

However, if you follow several or even all of the tips that we are about to list, the chances of stopping cichlids from being aggressive bullies decrease significantly.

1. Mix Cichlid Species – Coloration

One of the things that you can do in order to reduce cichlid bullying and aggression is to make sure to mix cichlid species in your tank.

This applies particularly to varying colorations. Cichlids see the same members of their species as direct competitors, and will therefore bully other members of their own species.

Therefore, make sure to have varying cichlid species with different colors and patterns in the tank. The more diverse the colors are, the less likely the cichlids are to be aggressive bullies toward one another.

colorful cichlid
Image Credits: Arunee Rodloy, Shutterstock

2. The Water Column & Aquarium Zones

Something else to keep in mind is that although many cichlids do like the bottom of the tank and the bottom third of the aquarium in general, not all cichlids do.

The more cichlids (and fish in general) you have occupying the same level or zone in the water column, the more likely they are to be aggressive.

Therefore, try to get different cichlid species that tend to occupy different zones in the aquarium, some at the bottom, some in the middle, and some at the top. If you can spread them out a bit, they’re much less likely to be aggressive.

3. Horizontal Space

Related to the above point, cichlids care way more about horizontal space than about vertical space. Therefore, in order to reduce cichlid aggression, one of the best things that you can do right from the get go is to get them a long and wide tank.

Tank height does not make much of a difference here. For a cichlid only or for a community fish tank with cichlids, you are much better off getting a tank that is long and wide, but has limited height.

aquarium with cichlids
Image Credit: Frantisek Czanner, Shutterstock

4. Change the Setup When You Add New Cichlids

This point applies specifically to when you add new cichlids into a tank that already has cichlids in it. These fish are quite territorial, and they will get attached to or protective of certain things in the aquarium. Each cichlid will develop and guard its own territory.

Therefore, to stop bullying and aggression between cichlids, when you add new ones into the tank, change the aquarium setup.

Change the scenery, add some new stuff and take out some of the old, or just rearrange the tank decorations. This will ensure that no cichlid has the time to become overly territorial over any one location in the tank.

5. Slight Overcrowding

Something that you want to do with any cichlid tank, whether a community or a cichlid only tank, is to slightly overcrowd it.

Now, this probably goes against everything that you have been taught about keeping fish. However, it actually works wonders in cichlid tanks.

The more overcrowded a cichlid tank is, the busier and faster paced the environment will seem. This in turn makes it more difficult for any cichlid to focus their attentions on any one fish.

If a cichlid cannot focus on a single fish for bullying, the chances of it occurring are greatly reduced.

school of cichlid
Image Credit: david6239, Pixabay

6. Keep them Well Fed

One of the main reasons why cichlids become aggressive is related to their naturally aggressive nature, specifically their drive to compete for food. Cichlids, in nature, live in very competitive environments where they must constantly compete for food.

Therefore, if your cichlids are not extremely well fed and satiated at all times, they will absolutely become aggressive and territorial in order to protect the food which they perceive to be theirs.

Simply put, feed your cichlids often and a lot, and this should help to curb bullying.

7. Limit the Number of Males

Whether it comes to the world of humans or fish, men have a tendency to compete with each other, specifically for females.

Simply put, the more male cichlids you have in comparison to females, the more bullying and aggression there will be. It is a good idea to limit the number of males in the tank, with a good ratio being three females to one male, or two females for every male at the very least.

This way, each male cichlid will have several females to choose from, so to speak, and that will help to drastically reduce aggression and bullying.

Single flowerhorn cichlid fish with nuchal hump in an aquarium
Image: Noppakit 77, Shutterstock

8. Good Cover

Another thing that you can do in order to reduce cichlid bullying in your aquarium is to provide the cichlids with plenty of cover and hiding spaces.

If they feel like they have enough room, a space that is their own, and a place to hide and to get some privacy from other fish, the less likely they are to be bullies. Therefore, having plenty of plants, rock caves, and hollow driftwood is called for.

9. Add New Fish in Groups

If you add new fish into a tank that already has cichlids in it, the less fish you add, especially if you add just one, the more likely those new fish are to get bullied.

Therefore, try adding at least three or four fish at a time. The more you add at once, the less likely individuals are to be singled out and targeted by some mean cichlids.

colorful cichlids in aquarium
Image Credit: Arunee Rodloy, Shutterstock

seashell dividersDo African Cichlids Kill Each Other?

If you have African cichlids, and you don’t follow any of the tips that we have outlined above, if they don’t have enough vertical space, if they don’t have enough food, if there are too many males compared to females, and so on and so forth, then they are likely to be aggressive towards one another, especially where males are concerned.

This can sometimes result in the death of some of the cichlids. In some cases, adult males may even try to eat juveniles, particularly male juveniles. In case you are wondering, yes they do have teeth!

african cichlid
Image Credit: ArtEvent ET, Shutterstock


What Are The Least Aggressive Cichlids?

There are various types of cichlids that are known for being fairly peaceful and non-aggressive, and these include the following.

  • Bolivian ram cichlid.
  • Keyhole cichlids.
  • Blue Acara cichlids.
  • Yellow lab cichlids.
  • German blue ram cichlids.

fish divider


The bottom line is that cichlids are by nature aggressive fish and they can be very territorial. However, if you take the steps as outlined above, you should be able to curb or even fully eliminate cichlid aggression in your tank.

You Might Also Be Interested In:

Featured Image Credit: Kraipitch Supyuenyong, Shutterstock

Related Articles

Further Reading

Vet Articles

Latest Vet Answers

The latest veterinarians' answers to questions from our database