A stunning, large schooling fish native to the Congo River basin. Known for their iridescent rainbow colors and active swimming behavior. Despite their size, they are notoriously peaceful and can be skittish, requiring ample swimming space, dim lighting or floating plants, and peaceful tank mates. Avoid keeping with fin-nippers.
At a Glance
Tank Requirements
Water Parameters
Temperament & Compatibility
Available Varieties
Each variety inherits the species defaults above. Only differences are highlighted.
Standard (Mixed School)
A standard mixed group of males and females. Congo Tetras are best kept in mixed-sex schools to encourage natural behavior and full male coloration.
Same care requirements as the base species
Also known as: Unsexed, Juvenile
Male
Males are larger, display highly vibrant iridescent colors (blue, red, gold), and develop long, feathery extensions on their dorsal and caudal fins.
Differs in 1 trait from base species
Also known as: Male Congo, Show Male
Female
Females are significantly smaller, with a plumper belly, much shorter fins, and more subdued silvery-gold coloration compared to males.
Differs in 1 trait from base species
Also known as: Female Congo
Albino
A selectively bred albino/platinum morph lacking dark pigments. Males retain some iridescent colors and long finnage, but the body is primarily white/pink.
Differs in 1 trait from base species
Also known as: Albino Congo Tetra, Platinum
Congo Tetra Care Guide Summary
The Congo Tetra, scientifically known as Phenacogrammus interruptus, belongs to the Characins family group. Adults reach a maximum size of approximately 8.5 cm and have a compressed body shape with a moderate growth rate. Classified as peaceful, this species primarily occupies the mid-level and surface zones of the aquarium and produces a low level of biological waste.
To thrive, the Congo Tetra requires a freshwater only aquarium with a minimum volume of 110 litres and a tank length of at least 90 cm. Water temperature should be maintained between 23°C and 28°C, with a pH range of 6–7.5 and a general hardness of 3–18 dGH. A moderate water flow is preferred.
The Congo Tetra is a rewarding species to keep, provided its core environmental needs are met. This species is available in 4 varieties: Standard (Mixed School), Male, Female, and Albino. Each may differ slightly in size, temperament, or care needs, so it is worth checking the specific requirements of the variety you plan to keep.
Congo Tetra Habitat Setup
When setting up an aquarium for the Congo Tetra, a moderate water flow best suits their natural preferences. Because this species occupies the mid-level and surface zones, the aquarium layout should prioritise adequate surface area with floating cover to make them feel secure near the waterline and open swimming space in the centre of the tank for free movement. Useful additions include dense planting to provide cover, break sightlines, and reduce stress and floating plants to diffuse overhead light and create shaded areas. Keepers should note that a tight-fitting lid is essential, as this species is a known jumper.
Congo Tetra Compatibility Notes
Classified as peaceful, the Congo Tetra is a schooling species that feels most secure in a sizeable group, where natural shoaling behaviour reduces stress and brings out their best colours. Selecting tankmates that favour different water layers from the mid-level and surface zones can help reduce competition and territorial overlap.
Frequently Asked Questions About Congo Tetra
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