Maximum size : 6 cm

Copei Tetra - Moenkhausia copei : Complete Fish Profile & Care Guide

Table of contents


The captivating and sociable Copei Tetras (Moenkhausia copei)! are peaceful community fish and are truly a delight to observe. As natural schooling creatures, they flourish when housed in larger groups of at least ten individuals, showcasing their true colours and exhibiting more authentic behaviour. Prepare to be enthralled by the enthralling dynamics of a mixed-gender group, slightly favouring females, as the males establish hierarchical structures and tirelessly vie for the attention of their female counterparts.

To create an optimal environment for Copei Tetras, a densely planted aquarium with a sandy substrate and a scattering of dried leaves on the bottom is highly recommended. These vibrant tetras also thrive in spacious tanks with subdued lighting, providing them with ample swimming space to express their natural instincts. Notably, Copei Tetras seamlessly coexist with various species in a community aquarium, particularly South American characins and bottom-dwelling companions.

However, avoiding housing these remarkable tetras alongside significantly larger or more aggressive species is crucial. Doing so may induce stress and competition for food, compromising their overall well-being. With their sleek, silvery bodies adorned with a shimmering yellowish gold sheen along the lower half, Copei Tetras effortlessly captivate onlookers. Adding to their charm, these fish boast vivid red hues on their caudal and adipose fins. While the dorsal fin of some individuals may display touches of colour, their pectoral, pelvic, and anal fins typically remain transparent, further enhancing their ethereal appearance.

Copei Tetra Photos

Sexual Dimorphism

Distinguishing between male and female Copei Tetras is a relatively straightforward task. Males typically exhibit a slimmer physique and boast more vibrant colours compared to their female counterparts. In breeding conditions, a distinct humeral spot is an identifiable characteristic of the males. On the other hand, females tend to be slightly larger in size and possess rounder bodies when compared to males.

Quick Facts

Scientific NameMoenkhausia copei
Year Described1882
Other NamesTetra Copei, Red Tail Tetra
OriginsVenezuela , Peru
Max Size6 cm
Aquarium LevelMiddle - Top
DifficultyBeginner - Intermediate
Best kept asGroups 10+
Diet & FeedingOmnivore
LifespanUp to 5 Years

Water Parameters

Water TypeFreshwater
pH 6.0 - 7.5
GH 10 - 20
TDS 18 - 268
Ideal Temperature
72 - 79
22 - 26

Natural Habitat

Copei Tetras are exclusive inhabitants of South America's awe-inspiring Rio Orinoco and Amazon River Basin. Within this remarkable habitat, a tapestry of colour variations awaits your exploration. From the vibrant red hues showcased by their Venezuelan counterparts to the alluring light orange tones adorning those from Peru, the Copei Tetras captivate with their diverse palette.

Venturing further into their natural abode, these Tetras claim their domain in moderately fast-flowing, shallow stretches of pristine rivers, where crystal-clear waters shimmer over sandy bottoms. Seek out their presence amidst secluded alcoves, where submerged trees and lush aquatic vegetation form havens of refuge and exploration. It is within these sanctuaries that the Copei Tetras establish their vibrant presence, harmonizing with the decaying remnants of nature and finding solace in the embrace of their aquatic haven.

 Orinoco - Venezuela
Venezuela Flag


The successful reproduction of Copei Tetras in captivity presents a noteworthy challenge. However, with optimal conditions, these Moenkhausia species can spawn naturally in a community aquarium, yielding a small number of fry without human intervention. It's important to note that, like other Tetras, they follow the characteristics of egg-scattering free spawners, exhibiting no parental care. Therefore, setting up a separate breeding tank is recommended for those seeking to maximize fry production.

The tank should be dimly lit with well-established water and abundant plant life to create a suitable breeding environment. Alternatively, spawning mops can serve as adequate substitutes. Additionally, conditioning the breeding pairs with ample live, frozen, or freeze-dried foods such as bloodworms or mosquito larvae will promote successful reproduction. When females are ready to spawn, their increased activity in the tank and gentle collisions with the males will become apparent. Subsequently, females will navigate among the plants, scattering their eggs, while the males diligently follow, fertilizing them.

Typically, the females will attach the eggs to the plants, although some may descend to the tank bottom. During a single spawning event, females can lay several hundred eggs. Once the females have completed the egg scattering process and the males have fertilized them, removing the adult fish from the breeding tank is advisable. They will have no further involvement with the eggs and may consume them if given the opportunity. Maintaining a dark and light-free environment is crucial, as Tetra eggs and fry are particularly light-sensitive.

Under favourable conditions, the eggs will hatch within 24 to 48 hours, depending on water quality and temperature. Approximately three to four days later, the fry will begin to swim freely. After the first week, a gradual increase in lighting can be implemented. Initially, the newly hatched fry will sustain themselves on their yolk sacs. However, once they have absorbed their yolk sacs and become free-swimming, providing them with infusoria or rotifers is recommended. As the fry grows, their diet can transition to include baby brine shrimp and crushed flakes.

By diligently attending to the specific requirements of breeding Copei Tetras, you can foster the growth and development of this delicate fry, ensuring a successful and rewarding breeding experience.

Diet & feeding

Copei Tetras sustain themselves on a diet comprising insects, micro-crustaceans, and plant matter in their natural habitat. However, in a captive setting, these tetras exhibit a versatile appetite and readily consume various forms of aquarium foods. High-quality dried foods such as flakes, granules, and pellets are readily accepted by Copei Tetras. Nonetheless, for optimal colouration and overall health, it is advantageous to supplement their diet with ample live and frozen options. This can encompass nourishing selections like blackworms, bloodworms, daphnia, and brine shrimp, enriching their feeding regimen and promoting their well-being.

Other Tetras of interest