Procyon Tetra
Hyphessobrycon procyon
This species inhabits the Rio Tapajós basin in Brazil. It is found primarily in forest streams (igarapés) characterized by blackwater conditions, slow.
Water Temperature
23 - 27 °C
pH Value
5 - 7
Water type
Freshwater
Tank level
Bottom and middle
Adult size
3.5 cm
Minimum tank volume
>= 60 L
Minimum group
>= 6
GH
2 - 8 dGH
KH
1 - 4 dKH
TDS
40 - 160 ppm
Conductivity
63 - 250 uS/cm
Species description
Geographical Origin and Habitat: This species inhabits the Rio Tapajós basin in Brazil. It is found primarily in forest streams (igarapés) characterized by blackwater conditions, slow current, and a substrate covered with decomposing leaf litter.
Taxonomy and Morphology: A member of the Characidae family, it is a small tetra growing to a maximum size of 3.5 cm. It features a streamlined, typical tetra-shaped body with a compact structure.
Social Behavior: A peaceful and schooling fish. To prevent shyness and encourage natural activity, it must be kept in a group of at least 6-8 individuals.
Coloration and Sexual Dimorphism: Features a semi-translucent body with bronze to orange highlights and a distinct diamond-shaped dark spot on the tail base. Males tend to have longer, more pointed dorsal and anal fins.
Care, breeding and tankmates
Aquarium Setup: Needs a tank of 60 liters minimum. Design with a fine sand bed, driftwoods, and dried leaves (like oak or beech). Subdued lighting using floating plants is recommended.
Diet and Feeding: Accepts high-quality dry foods, but live or frozen micro-foods such as brine shrimp and cyclops should form a major part of its diet to support optimal health.
Water Quality: Demands stable conditions. Acidic pH of 5.0-7.0, soft water with GH 2-8 dGH, and stable temperature of 23-27°C. The addition of humic substances is highly beneficial.
Compatibility and Cohabitation: Suitable only for quiet community tanks with small tankmates like Corydoras, other peaceful tetras, and dwarf cichlids. Avoid aggressive or large fish.
Aquarium Breeding: Rarely documented in home aquaria. It requires extremely soft, acidic water, dimmed environment, and feeding the fry with microscopic foods like infusoria.
Risks and Diseases: Highly susceptible to shock from sudden water parameter changes. Keeping water clean and stable is paramount. Use a lid as they can jump.
Geographic Origin and Distribution
This species inhabits the Rio Tapajós basin in Brazil. It is found primarily in forest streams (igarapés) characterized by blackwater conditions, slow current, and a substrate covered with decomposing leaf litter.
Origin
Extra-Amazon South America
Fish profile
- Temperament
- Peaceful
- The temperament of Hyphessobrycon procyon is overwhelmingly peaceful, making them an exemplary model of a docile community fish. They are not prone to fin-nipping or aggressive territorial disputes, provided they are kept in appropriately sized schools that allow them to establish a natural hierarchy. While males may occasionally engage in harmless sparring displays to establish dominance or impress females, actual physical damage is exceedingly rare. Their gentle nature ensures they will not harass slower-moving tank mates, fostering a tranquil and harmonious aquatic environment.
- Diet
- Omnivore
- In their natural habitat, Hyphessobrycon procyon are micro-predators and foragers that feed on tiny insects, crustaceans, and various zooplankton. Within the aquarium environment, they readily accept high-quality dry foods such as micro pellets and crushed flakes designed for small tropical fish. To ensure their best coloration and overall health, their diet should be regularly supplemented with live or frozen foods like Daphnia, newly hatched brine shrimp, and bloodworms. A varied diet prevents nutritional deficiencies and mimics their diverse natural foraging behavior.
- Life expectancy
- 3-5 years
- In a carefully managed home aquarium, Hyphessobrycon procyon (commonly known as the Procyon Tetra) has an average life expectancy ranging between three and five years, and can exceed this threshold under exceptionally stable conditions. Being a peaceful and gregarious species, it must be kept in a school composed of at least six or eight individuals to promote natural behaviors and minimize stress levels. It thrives in soft and slightly acidic water, with a pH value between 6.0 and 7.0 and an optimal temperature between 23 and 28 degrees Celsius. The aquarium setup should include dense vegetation, bogwood releasing tannins, and gentle filtration with a moderate water flow. The ideal nutrition is based on alternating high-quality microgranules and small-sized live or frozen food, such as daphnia and brine shrimp, which is essential to keep its colors bright and strengthen the immune defenses.
- Adult size
- 3.5 cm
- The catalog's scalar value is 3.5 cm. The FishBase SPECIES table (v25.04 snapshot) source reports a maximum adult measurement of 3.22 cm for this species, recorded as standard length (SL). The taxonomic record consulted is Hyphessobrycon procyon (v25.04); male or unsexed record. These figures are not interchangeable: the first is the profile's editorial reference, whereas the second is a published maximum under a specific measurement convention; differences among sources can reflect sex, population, life stage and measuring method.
- Sex ratio
- School
- While Hyphessobrycon procyon does not strictly require a specific male-to-female ratio, keeping a mixed group with a slight majority of females is generally recommended. Having more females helps distribute any amorous or territorial chasing behavior from the males, preventing individual females from becoming overly stressed. In larger schools of ten or more, the sex ratio becomes less critical as aggression and attention are widely dispersed throughout the group. Observing a healthy mix of both sexes also allows aquarists to enjoy the more intense, vibrant coloration that males display when showing off to the females.
- Feeding frequency
- Twice daily
- To maintain optimal health and vitality, Hyphessobrycon procyon should ideally be fed small portions one to two times per day. It is important to only offer an amount of food that the entire school can completely consume within two to three minutes. Overfeeding can lead to poor water quality, algae outbreaks, and potential health issues for these small fish. Providing a fasting day once a week can also be beneficial to clear their digestive tracts and replicate natural food scarcity.
- Bioload
- The bioload produced by Hyphessobrycon procyon is generally considered to be quite low due to their small adult size and active metabolism. These tiny fish do not generate significant amounts of waste, making them excellent candidates for densely planted setups or nano aquariums when kept in appropriate numbers. However, a proper filtration system and regular water changes are still essential to maintain optimal water quality. If kept in very large schools, their cumulative bioload can increase slightly, but it rarely overwhelms a standard, cycled aquarium filter.
- Flow
- Strong
- Coming from environments ranging from sluggish tributaries to moderately flowing streams, Hyphessobrycon procyon appreciates a gentle to moderate water flow in the aquarium. They are not built to constantly battle strong, torrential currents, which would quickly exhaust them and induce significant stress. Employing a spray bar or directing the filter outflow towards the tank glass can help diffuse the water movement effectively. Providing calmer resting areas among dense vegetation allows them to retreat and conserve energy whenever needed.
- Jump risk
- Yes
- Like many small, active species, Hyphessobrycon procyon possesses a moderate risk of jumping out of the aquarium, especially when startled or during the initial acclimation period. Sudden changes in lighting, aggressive tank mates, or sudden movements outside the tank can easily spook them into a leaping reflex. It is highly recommended to keep the aquarium securely covered with a tight-fitting lid or a specialized mesh screen. Floating plants can also be added to the surface to help them feel more secure and deter jumping behaviors.
- Reproduction
- Oviparous
- Hyphessobrycon procyon belongs to the category of egg-scattering fish, meaning they broadcast their eggs freely without providing any subsequent parental care. In a dedicated breeding setup, dim lighting, very soft, acidic water, and an abundance of fine-leaved plants or spawning mops are required to encourage spawning. The adult fish are notorious egg-eaters and must be removed from the breeding tank immediately after the spawning event concludes. Once hatched, the microscopic fry require infusoria or specialized liquid fry food until they are large enough to accept baby brine shrimp.
- Compatibility & tankmates
- Community
- Hyphessobrycon procyon is an incredibly peaceful and sociable schooling fish that makes a fantastic addition to most community aquariums. They thrive when kept alongside similarly sized, non-aggressive species such as Corydoras catfish, small rasboras, and other docile tetras. It is crucial to avoid housing them with large or predatory fish that might view them as a quick snack, such as larger cichlids. Maintaining them in a group of at least six individuals will help them feel secure, significantly reducing any potential stress or shyness.
- Tank level
- Middle/Bottom
- In the aquarium, Hyphessobrycon procyon primarily inhabits the middle to upper levels of the water column, rarely venturing completely to the bottom unless searching for fallen food. They are enthusiastic swimmers that appreciate plenty of open swimming space in the center of the tank to dart around in their schooling formations. Providing tall background plants or floating vegetation will give them the upper-level cover they desire without encroaching on their preferred swimming zones. Their mid-water presence makes them an excellent choice for adding active, colorful movement to the central focal point of a planted setup.
Scientific Parameters & Models
FishBase
Window to the official scientific data of the species
Data synced on: 06/15/2026
- Trophic level
- 2.9 ± 0.3 se
- Resilience
- High (less than 15 months)
- Phylogenetic uniqueness (PD50)
- 0.5
- Bayesian Length-Weight
- a = 0.01995, b = 3.01
- VulnerabilityLow vulnerability (10 / 100)
Image gallery
Licensed images linked to the species or, when marked, to the closest representative taxon.
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