Clad with the luminous patterns of the rainbow, the congo tetra brings an iridescent hue to your aquarium. The movement of a school of these mid-sized freshwater aquatics creates mesmerizing colorful hues in your aquarium.

The perk of getting them inside your tank is that they don’t demand high maintenance. You can be a successful fish parent by providing them the needful.

Largest among all tetras, these tetras use their vibrant colorings for courtship purposes. With all this richness and relatively low demands, they make a perfect aquarium fish.

However, although easy to maintain, they also require a perfect environment to thrive with brilliant hues. By imitating the wild in your tank environment, you can make it to the fullest.

If not, you still have to maintain the minimum requirements to make your tetras happy and healthy. Hopefully, this definitive guide will come in handy in this respect.

Quick Fact: Like most tetra fish, congo tetras also have teeth.

An Overview of Congo Tetras

Quick Species Facts
Scientific Name Phenacogrammus Interruptus
Common Names Congo Tetra, African Tetra
Family Alestidae (African tetras)
Origin Congo river basin in central Africa
Average Lifespan 3 to 5 years
Average Size 6-8 cm
Type Freshwater Fish
Congo Tetra: A Definitive Guide to Care

Origin and Habitat

These aquatics originated from the mid-Congo river basin in the Democratic Republic of the Congo and the Republic of Congo.

These aquatics are found in tributaries, marshes, pools, and streams around the Congo river basin. They prefer dark, murky, and slightly acidic water while in the wild.

Congo tetras came into view for the first time in the year 1949.It took them a long time to gain popularity as an aquarium species because of their difficult breeding conditions.

For quite a long time, fish hobbyists had to depend on the wild to get these colors for their home tanks. After perfecting the breeding line by Florida Fish farms during the 1970s, the aquarists started importing them as ornamental fish species for their tanks.

How Big do Congo Tetras Get?

Males usually grow to a maximum of 8 centimeters (3 inches), whereas females grow to 6 centimeters (2.5 inches).

Remarkably, you’ll find them growing up to as long as 4 to 4 ½ inches in the wild. But, such growth is not attainable in captivity.

Appearance and Color

Males have a relatively higher commercial value due to their brighter color. Even research has been going on to “increase the percentage of the male sex of Congo Tetra fish.”

As for the appearance, they reveal a long flat shape with partially transparent long fins and large scales. Those long fins make them even more gorgeous with a greyish-violet color with white edges.

From a distance, it looks like a rainbow is glimmering from your congo tetra tank. However, with a closer look, you’ll notice that vertical patterns with the dominance of blue, red, and yellow-gold cover their bodies from the head to the fins.

Quick Fact: Did you know that this fish species shows fast growth? The fry reaches a length of 1 inch in around two weeks. It grows to be 2 inches in the next three months.

Types of Congo Tetra

Sometimes, based on their distinguishing color patterns, certain peculiar ones among them are put into different categories, such as the following —

  • Albino congo tetra
  • Cherry red congo tetra
  • Blue diamond congo tetra
Types of Congo Tetra

You will instantly see the difference when you carefully look at these categories. They demonstrate shades according to their names.

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While albinos show a lighter coloration, cherry red or red congo tetras emit a dominant red hue. On the other hand, the blue diamond tetras glimmer with a turquoise shade.

Maximum Life Expectancy

Like most aquarium fish species, these tetras don’t live long. The maximum life expectancy of these aquatics varies from 3 to 5 years.

Overall, the complete lifespan of these underwater creatures depends on the tank environment and the food you are feeding your aquatic pets.

How to Sex Your Congo Tetras?

If you look at these fish from the standpoint of male vs. female, you’ll see that the males are brighter in color than their female counterparts.

Males of this species are more vibrant with brighter hues when kept in the natural environment.

While males show multiple colors with the dominance of turquoise-blue hues, females often omit yellowish-golden shades with weaker bluish-silver and reddish shimmers.

Apart from this, the differences regarding their size and the fins are also evident. The dorsal fins of the males are relatively longer than the females, revealing an eye-catching pattern while swimming.

The male tetras are slightly longer compared to the females. Females are chubbier than males, especially when they are ready for breeding.

Thus, sexing them is not difficult with keen eyes.

Sale Price and Availability

Congo tetras are for sale at varied prices, starting from around $6-7 and going up to approximately $40. They are widely available in the market, considering their extensive breeding and export.

As a highly admired breed among aquarists, they can be found through both online and offline sources.

Care Guide

Quick Care Facts
Care Level Easy
Social Behavior Sociable and schooling
Temperament Peaceful and active
Diet Omnivorous
Breeding Not easy

Food and Diet

  • An appropriate diet rich in protein and fatty acids will help your tetras to grow and retain their lustrous tinctures.
  • As omnivores, they feed on plant materials, small insects, worms, crustaceans, algae, zooplankton, etc., in their wild habitat.
  • They are not picky eaters. Your fish will be alright with both live and frozen food. Hence, while in captivity, you can feed them varieties of food to make a balanced diet full of nutritional values.
  • To recommend some, the tetras will love flakes and pellets. Apart from that, some high-protein treats such as bloodworms, brine shrimp, daphnia, and Tubifex worms are their favorites.
  • You can also feed them fresh vegetables to ensure that they can grab the appropriate nutritional value out of their diet.
  • Don’t forget to feed your fish several times a day. If your tetras are biting the plants inside the tank, it can indicate that they are not getting the required amount of food.

Quick Fact: These fish types may show shy behavior during feeding time. They may not come to their food in case people are around.

General Behavior

  • Congo tetras are a schooling fish type with peaceful nature. Despite that, they might frighten small or shy species with their hyperactive nature.
  • Although amiable, it’s good not to keep them with aggressive species. They won’t do well with such species. Your tetras will look for hiding spaces if you put them in such an inconvenient situation.
  • They prefer to swim around the tank in groups throughout the day.
  • These beauties often show interest in roaming around the middle and top areas of the tank.

Pro Tip: Since they are schooling fish, they might get frightened and stressed if not maintained in numbers. So, try to keep them in groups of five or more to build their comfort zone.

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Breeding of Your Congo Tetra

Now, how to breed congo tetras?

Well, you can either breed the min pairs or in a school. But, considering the lack of parental feelings in this species, it’s wise to set up a separate 20-liter tank.

But how to set up a breeding tank?

The following list of tips will provide you with proper guidance regarding it.

  • To set up the breeding tank, consider adding soft, acidic water to obtain good results.
  • Congo tetras have a tendency to eat their own eggs. Adding a peat substrate to the tank bottom will protect the eggs from the reach of the parents. Along with that, you can further add breeding plants if you wish.
  • Don’t forget to adjust the temperature of the breeding tank between 76-80°F along with dim lighting.
  • Once the peat substrate is spread well throughout the bottom of the tank, you are ready to introduce the breeding couple into it.

Quick Fact: These aquatics prefer to spawn in a brightly lit aquarium. This behavior is not identical to many other tetras.

Once you introduce the breeding couple to the tank, the female will slowly move forward to the peat substrate, followed by the male. And then, the spawning will start.

During the process, the female tetra will lay up to 300 and even more eggs light brown in color. The eggs will go down and sit on the bottom.

The rest is easy. Once the spawning process ends, return the pair to the main tank and wait for the eggs to hatch. It takes around 6 to 8 days for the eggs to hatch and the fry to appear.

In the first phase, you can feed the fry infusoria. After a few days, they will be able to eat newly hatched brine shrimp or rotifers. It will take around two weeks for the fry to be large enough to take standard fish food.


Congo tetras are often considered hardy fish as they are not prone to species-specific diseases when well-kept.

However, it doesn’t mean they will be alright without proper care. As they are sensitive regarding the water parameter, inappropriate water conditions or low maintenance will lead to stress. This stress might expose them to ich – a fatality for aquarium fish.

By maintaining proper care, you can effectively protect them from such illnesses.

To know more about common diseases related to aquarium fish and their effective treatments, visit our complete guide.

Tank Care

Quick Tank Facts
Minimum Size 30 Gallons
Water Temperature 23°C – 26°C (73-79°F)
Water Hardness 5 – 19 dH
Lighting Dim lighting of 12-14 hours
pH Level 6.0 – 8.0

Ideal Tank Size

To keep these fish in captivity, you need a minimum tank size of 30 gallons.

Although these fish are not large, this tank size is required for their schooling nature. Otherwise, their happiness and convenience will be compromised.

Tank Set-up:

The best thing about this particular fish is that you don’t require a very grand arrangement to keep these mid-sized aquatics happy. The fundamental necessities will keep them happy, healthy, and comfortable.

Still, providing them with a healthy tank set-up will erase the chances of them being stressed, diseased, or pale-colored.

Thus, let’s go deep into the complete tank set-up procedure for your underwater pets.

  • Plants: As for the plants, you can pick both live and artificial plants for your congo tetra tank. Plants in the tank provide them with space to lay their eggs. Apart from that, live plants will help adjust the nitrate levels of the tank water. Note that your tetras might eat soft plants. To avoid that, you can choose hard plants like Anacharis, Java Fern, Water sprite, etc.
  • Lighting: In the wild, these aquatics prefer dark, murky water. Dim lighting in the tank is recommended to mimic that environment. Adding floating plants to the aquarium will also help protect the inhabitants from the light.
  • Substrate: It is seen that these fish species are naturally drawn toward dark substrates. To imitate that in captivity, you can go for a dark, sandy substrate by adding mud, sand, or silt at the bottom.
  • Oxygen and Filtration: A sufficient filtration facility is essential to keep the waste levels low in your tank. You can consider a canister filter or a carbon filter. On the other hand, adding live plants to the aquarium helps keep the ammonia and nitrate level in check, thereby maintaining an appropriate oxygen level.
  • Decor: Decorating your congo tetra tank is preferable to maintain the aesthetics of the tank. Apart from that, the decorative materials provide many hiding places for your pets. So, for decoration purposes, you can pick driftwood, artificial caves, rocks, etc.
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Expert Tip: When adding plants to the tank, ensure that the proportion of plant-covered area and open space is maintained well. Since they love to swim around in large groups, it needs enough open space to do so.

Water Parameters

They prefer soft, acidic water. So, adjust the water condition to a 6.0 to 8.0 pH level and a dH range of 5 – 19. The ideal water temperature for congo tetra should remain between 73-79°F.

Stability in water conditions is essential to protect your fish from any prospective fatality. Since they prefer soft water, ensure a slow water flow.

Maintaining these ranges is essential, as these beautiful fish species belong to a region where the waters share these qualities. Coming from the tropics, they are habituated in warmer black water with low minerals and a particular range of acidity. Thus, maintaining a near-natural habitat will keep them intact.


Congo tetras are community fish without any tendency to harm others. You can add any other fish to the tank, and they will not come in their way.

But, they might be uncomfortable with aggressive species resulting in hiding themselves. So, you must be mindful of other species to add to a tank with this fish type.

Refer to the following list of compatible tank mates to keep in your tetra tank without getting worried.

  • Other tetras and rainbowfish
  • Corydoras
  • Mollies
  • Celestial Pearl Danio
  • Synodontis
  • Dwarf Cichlids
  • Chili Rasbora
  • Platies

And there are even more of them to choose from.

Pro Tip: Congo tetras are more sizable than other tetras. It is recommended to avoid keeping them with the smallest tetras, like neon tetras or adonis tetras. Besides, aggressive fish, including certain cichlids, should not be kept with congo tetras.

Frequently Asked Questions

Can congo tetras live with sharks?

Most aquarium sharks, including the rainbow and the red finned shark, are hostile towards small fish species like tetras. So, it’s not recommended to keep them with sharks.

How many congo tetras should I add to a 20-gallon tank?

Generally, it is recommended to keep a minimum of a 30-gallon tank for a school of congo tetras. Still, some aquarists have seen success in a 20-gallon tank. As this species is a community fish, can add at least 4-6 individuals to keep them happy and comfortable.

Are congo tetras fin nippers?

The possibility of them being fin nippers can’t be avoided altogether. Although they are not as notorious fin nippers as neon tetras, these largest tetras also might portray a nipping habit.

Summing It Up

So, now the question is: Should you get them home?

And the obvious answer is yes!

Congo tetras are a species suitable for both beginners and experienced aquarists. As a beginner, adopting this species will give you enough room to explore the world of fish-keeping.

If you have a tight budget, they are the right pick. Because they can do with the minimum requirements without hefty investment or an extravagant set-up as it is necessary for some other ornamental fish species like a discus.

So, if you are getting a peaceful, gorgeous beauty at a reasonable expense and low maintenance needs, why look elsewhere?

About the Author

Victoria Lamb

Victoria is a freshwater aquatics specialist, fish keeper, and amphibian enthusiast. She has had more than 6 years of experience caring for aquariums and keeping several fish species, and her home boasts of 3 aquariums and a garden pond. Her goal is to educate fish owners on raising healthy and happy aquatic pets.

Career Highlights:

  • Has worked with several aquarium manufacturers as a consultant
  • Organized and hosted workshops on freshwater fish keeping at retail stores, educational facilities, and libraries
  • Released content for the amphibian community through her writings

Educational Highlights:

Bachelor of Science in Animal Behavior and Welfare

  • University of Lincoln, Lincoln, UK (2014-2018)

Writing Experience

Victoria has done ghostwriting for many aquarium and pet websites in the past. She has also worked for Canada's largest natural health magazine- ALIVE, with 300,000 monthly circulations as a freelancer. She had six published articles on animal behavior and welfare during her graduation for her thesis.

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