Are Cardinal Tetras Community Fish?

The Cardinal tetra is a beautiful little freshwater fish that has become very popular in the aquarium hobby. Being a vibrant red color, it is hard not to see the appeal of these fish. But, unfortunately, many people do not realize that there are some inherent risks when housing this type of fish with other types in an aquarium setting. And one of the common questions among the owners is whether Cardinal tetras are community fish or not.

Yes, you can actually house cardinal tetras in a community tank with other fishes. However, they are a little more high maintenance than some other species. Therefore it is important to ensure that you meet their needs before introducing them into your aquarium tank.

In fact, there are many successful community tanks where Cardinal tetras are one of the main inhabitants in the middle levels of the aquarium. So, in this blog post, you will find out how to successfully keep these fish in a community tank and the ideal conditions they need for their health.

Are Cardinal Tetras Community Fish?

The answer is not straightforward because there are always exceptions to rules. However, generally speaking, you should never keep cardinal tetras with small or shy tank mates. Cardinal tetras need to feel comfortable by being the top two inches of the tank. The length of the tank should be twice as long as it is tall and no less than 20 inches long for cardinal tetras to thrive.

Cardinal tetra fish also need places where they can hide from any potential threat or predator that might come along their way, such as larger predatory fish like bettas or cichlids, or even certain types of fish that are aggressive. As for tankmates, larger cardinal tetras can live with angelfish and gouramis in a community aquarium. Both species grow large enough so that the smaller cardinals can’t bully them.

What Are The Best Tankmates For Cardinal Tetras?

“Community” is a term that refers to the types of tankmates one can keep with their pet. The answer depends upon which species or type of fish you can find in your nearby pet stores.

The best tankmates for cardinal tetras are other small fish that will not nip at their tail fins. Some of them are:

  • Ember Tetras
  • Neon Tetras
  • Harlequin Rasboras
  • Rosy Barbs
  • Dwarf Gouramis

It would help if you never kept Cardinal tetras with larger, more aggressive fish. They will likely feel stressed and ill if you force them to live in an overpopulated tank. If you have a large school of cardinal tetras, it is best to add a few more cardinal tetras rather than one or two large fish.

How Can You Keep Cardinal Tetras Safe In Community Fish Tank?

The cardinal tetra is a small tropical fish that originates in the Amazon River basin. Most of these fish prefer to live alone or with another same-sized, similar species. Therefore, keeping them in community tanks requires more care than most other types of fish. Unfortunately, without proper care and protection, you can find yourself with a dead cardinal tetra.

Some of the things that you to consider to keep the cardinal tetra safe in a community fish tank are:

Optimum Water Parameters:

The cardinal tetra originates in the Amazon River basin, where water parameters can fluctuate. Therefore, you should ensure that your tank’s pH and temperature remain as close to those natural conditions as possible. This will help keep these fish safe from stress-related factors like disease and fungus, which can be common occurrences when keeping tropical fish.

Usually, the best water parameters to aim for are a pH of around six, temperature between 73 and 77 degrees Fahrenheit, and at least ten gallons per cardinal tetra. Although some people may recommend slightly lower or higher temperatures than that, those numbers should be the ideal conditions you want to strive towards as they will help keep your fish healthy.

Proper Tank Size:

Keeping your cardinal tetras in a community tank is not good unless you have at least 20 gallons of space. This provides them with enough water so they can swim around. But it prevents the other fish from getting too big and hurting them by accident (like spooking or startling).

Proper Filtration:

Cardinal tetras are very sensitive to changes in water chemistry, particularly chlorine. Therefore, a proper filtration system is a must for these fish because they need an environment that’s stable and balanced at all times. If you have too many cardinal tetras in your community tank or don’t use the right kind of filter, then you can find yourself with dead fish very quickly.

Proper Decorations:

Cardinal tetra fish are very light-sensitive, which means they prefer to have a darker environment. If you use brightly colored decorations in your community tank, the cardinal tetras will be more stressed out and won’t want to come out. It’s best to use darker colored gravel and rocks, or even some driftwood if you want.

Proper Food:

Cardinal tetras are tiny fish that eat tiny food like infusoria (bacteria), micro-worms (nematodes), daphnia, brine shrimp, etc. It would be best if you fed them small amounts of live food at least once a day. Feeding them too much will pollute the water, which could kill all your fish very quickly because they don’t have enough filtration to protect them from that kind of environmental change.

Proper Care:

Cardinal tetras are extremely sensitive due to their small size and delicate nature. As a result, they can’t handle rapid temperature changes, overcrowding in the tank, or any other abrupt environmental change. Their water also needs to be very clean because they are susceptible to bacteria growths.

These things require a lot more care than most fish owners expect when keeping a community tank. So it’s best to keep your cardinal tetras in a separate tank if you want them alive and healthy long-term.

How Does A Community Tank Differ From A Fish Only Tank?

A community tank is a type of aquarium that contains more than one species. In this setup, you can create your own unique ecosystem within the fish tanks environment. As a result, the fish will naturally establish their own hierarchy, so there should be no need to add aggressive species.

A fish-only tank contains only a single species. These tanks tend to be much easier to maintain and offer fewer maintenance requirements than their community counterparts, but this means they don’t provide the same kind of diversity as other setups.

What Are The Best Fish For A Community Tank?

It really depends on your personal preferences, but here are some suggestions.

Neon Tetras:

Neon tetras are famous for their relatively peaceful behavior. They are great for beginners and will do well in a wide range of water conditions.

Cherry Barbs:

They are an excellent choice if you’re looking to add variety because they come in such a diverse coloration. However, cherry barbs are very active. So, make sure that the tank has plenty of space to accommodate their needs. Besides this, they are a little nippy. Hence, they might not make the best choice for tanks with smaller fish in them.

Rummynose Tetras:

They are among the more popular tetra species because they are very active and look great in an aquarium. In addition, rummy nose tetras are peaceful enough that they should integrate well into community setups. They are also great for beginners because they are a few species that will readily breed within a community tank environment.


Swordtails are famous for being very easygoing. However, they are also pretty hardy fish, so they are ideal for those without much experience with aquariums in the past.

It is best to keep swordtails in groups of six or more because they tend to be a little bit aggressive when alone.

Convict Cichlids:

These cichlids are one of the more popular species because they are pretty hardy. However, they are also extremely active, so make sure you have plenty of space in your tank.

Usually, housing convict cichlids with other fish won’t bother them. However, they can eat live plants, so be careful if you like keeping them in planted tank setups.

However, sometimes they act very territorial and will fight with other convict cichlids. So, in such a case,e it is best to keep them alone or with a single partner of their own kind.

Cardinal Tetras:

Cardinal tetras are one of the most popular tetra species because they are extremely vibrant. In addition, they are quite hardy and can live well in groups of four or more.

But, Cardinal tetras are also somewhat sensitive and need pristine water conditions. Hence, it is best to keep them with other species that have similar requirements.

What Are Specific Types Of Fish Not Good For A Community Tank?

Aggressive fish can establish a dominance hierarchy within the tank. As a result, these fish might not do well when housed with other species, and they can also be very harmful to smaller or more passive community inhabitants.

Some of the most aggressive types of fish include:


Pikes are extremely territorial. They are very nippy. So, it is best to keep them in a tank with their own species. However, they might eat smaller fish like cardinal tetras in a community tank.


Cichlids are very aggressive. It is best not to keep them in a tank with other species of fish.  They are rarely compatible with other species.

Besides this, cichlids are also more likely to eat the plants of your tank when you house them.

Sharks And Rays

They will easily outcompete more peaceful inhabitants. These fishes can be extremely dangerous too. So, you cannot keep them in a community tank. Sharks and rays are not compatible with many other species and can eat smaller fish.


Overall, the cardinal tetra is a good fish for beginners because it’s hardy, durable, and peaceful. It’s also extremely colorful, which makes them appealing to many hobbyists at the same time.

Though Cardinal tetras are peaceful, keeping them in a community tank can be challenging. It is best to keep Cardinal tetras in schools of six or more to prevent the bullying of weaker ones by their tank mates.

We hope that this post helps you understand Cardinal tetras more.

Scroll to Top