Maximum size : 8.5 cm

Congo Tetra - Phenacogrammus interruptus : Complete Fish Profile & Care Guide

Table of contents


The Congo Tetra (Phenacogrammus interruptus) is a species that offers an intriguing combination of vibrancy and liveliness, making it a popular addition to any aquarium. Known for their dazzling and distinct hues, these fish appeal to both novice and expert aquarists. Congo Tetras exhibit a particularly striking sexual dimorphism; the males stand out with their long, flowing fins and a remarkable greyish-violet colour, while the females, although less flamboyant, captivate observers with their golden-yellow hues accented with shades of blue.

To ensure these Tetras' colours are showcased optimally, it's crucial to house them in an aquarium that closely mirrors their natural habitat. This includes plenty of plant life and hiding spots, soft and acidic water, and a strong circulation system. Suitable tankmates for these peace-loving Tetras include other non-aggressive species like Dwarf Barbs, Cichlids, Rainbowfish, Loaches, and Corydoras Catfish.

It's important to note that Congo Tetras, in their native habitat, tend to school in large groups. Therefore, it is beneficial to keep them in groups of at least six to maintain their natural behaviours. These fish are somewhat timid and prone to stress, so providing an environment with abundant hiding spots and ample swimming space can help them feel more secure.

Congo Tetras are relatively uncomplicated to feed, as they don't have specific dietary preferences. They are comfortable with various types of food, including live, frozen, and dried options. Maintaining a balanced diet for your Tetras is key; a mixture of high-quality dried food supplemented with regular servings of live or frozen food will keep them in good health and ensure their colours remain vibrant.

In conclusion, the Congo Tetra is a remarkable and peaceful aquarium inhabitant, effortlessly adding a splash of colour and dynamic activity. They are straightforward to care for and a solid choice for anyone interested in fishkeeping, regardless of experience level. With the right care and attention, these stunning Tetras will thrive and bring endless pleasure to their caretakers.

1 other variant of the Congo Tetra

Below is a list of Variant/Colour Morphs of the Congo Tetra

Congo Tetra Photos

Sexual Dimorphism

Identifying the gender of Congo Tetras is straightforward due to their distinct physical traits. Male Congo Tetras usually display a more vibrant colour palette, and they are generally larger than their female counterparts. Their dorsal and caudal fins are notably elongated, featuring striking white edges.

Conversely, female Congo Tetras exhibit a subtler colouration. They generally display a golden hue with a slight silverish-green undertone, and their size is typically smaller compared to the males. Furthermore, the females' fins are less ornate, presenting a clear distinction from the more extravagant finnage of the males.

Featured Male
Featured Female
Female Male

Quick Facts

Scientific NamePhenacogrammus interruptus
Year Described1899
OriginsDemocratic Republic of the Congo
Max Size8.5 cm
Aquarium LevelMiddle - Top
DifficultyBeginner - Intermediate
Best kept asGroups 5+
Diet & FeedingOmnivore
ReproductionEgg Depositor
LifespanUp to 5 Years

Water Parameters

Water TypeFreshwater
pH 6.2 - 7.2
GH 4 -18
KH 4 - 8
TDS 150 - 250
Ideal Temperature
75 - 81
24 - 27

Natural Habitat

The unique and captivating Congo Tetras hail exclusively from the upper regions of the River Congo, situated in the Democratic Republic of Congo, Africa. Their natural dwelling places are characterized by slow-moving and shaded water bodies such as rivers, streams, pools, and marshes. They exhibit a preference for murky, slightly acidic waters with dark substrates composed of sand, silt, and mud, in conjunction with aquatic plant life.

Interestingly, unlike many aquatic species, Congo Tetras do not favour habitats abundant with rocks or tree branches. This distinctive preference makes them a fascinating addition to any fish collection. As a fish enthusiast, introducing Congo Tetras into your aquarium is guaranteed to enhance its aesthetic appeal.

 Congo River - Democratic Republic of the Congo
Democratic Republic of the Congo Flag


Breeding Congo Tetras presents an intriguing challenge due to their seasonally-dependent spawning habits. Convincing a pair to spawn in captivity requires careful planning and conditions. Yet, with a suitable setup and optimal environment, successful breeding is achievable.

The first step is to create an encouraging environment. This involves a large aquarium filled with peat-filtered water under brightly lit conditions. Introducing substantial amounts of moss or a similar substrate is crucial as it serves as the spawning ground where the female lays her eggs.

The breeding process involves a fascinating dance by the male to woo the female. Once captivated, the female proceeds to deposit her eggs among the moss. Following the breeding, it is essential to separate the adults from the eggs because Congo Tetras have a propensity to eat their offspring.

Approximately a week post-spawning, you can expect the arrival of tiny fry emerging from the eggs. For their initial nutrition, they should be provided with infusoria for several days. About a week later, their diet can be broadened to include baby brine shrimp and microworm. By the time they reach two weeks of age, the fry should be sufficiently large to ingest powdered fish food.

Diet & feeding

Preserving the bright and vibrant hues of Congo Tetras requires a nutritional diet fed in ample amounts several times a day. They are amenable to a variety of food types, including live, frozen, and freeze-dried options. Examples of their preferred food include dried worms, bloodworms, daphnia, and green vegetables.

A well-rounded diet is fundamental for their overall health and colouration maintenance. It should encompass high-quality dried food like pellets, granules, and flakes, which provide essential nutrients to keep them in optimal health.

Nevertheless, diet plays a significant role in their behaviour towards their environment. In the absence of adequate plant-based nutrition, Congo Tetras might resort to nibbling on decorative soft plants in the aquarium, which could cause potential damage. Therefore, maintaining a balanced diet that incorporates an appropriate quantity of plant matter is crucial in preventing any undesired impact on the aquarium plants.

Frequently asked questions

Congo Tetras are active, schooling fish that require plenty of swimming space. A minimum tank size of 30 gallons is recommended, but a larger tank is even better.

ongo Tetras prefer soft to slightly hard water, with a pH between 6.0 and 7.5, a hardness from 5 to 20 dGH, and temperatures between 24 to 27°C (75 to 81°F).

Yes, Congo Tetras are generally peaceful fish and can be kept in a community tank with other non-aggressive species of similar size.

Males are more colorful, have longer dorsal and caudal fins, and are larger than females. Females are less colorful and have a rounder body shape.

Yes, they can. Congo Tetras are egg scatterers and the parents will need to be removed from the tank after spawning to prevent them from eating the eggs.

With optimal care and living conditions, Congo Tetras can live up to 3 to 5 years in captivity.

Regular water changes, a balanced diet, and a stress-free environment are key to their health. Provide plenty of cover in the form of plants or decorations to help them feel secure. Regular health checks can also help detect signs of illness early.

9 tank mate ideas for the Congo Tetra

Looking for some awesome tank mate ideas for your Congo Tetra? Look no further! Here are 9 of the most captivating and fascinating options that will liven up your aquarium!

Other Tetras of interest