Weitzman's Tetra
Hyphessobrycon weitzmanorum
A beautiful and small freshwater tetra native to the Upper Amazon basin, requiring soft, acidic water and peaceful tankmates. Its delicate appearance enriches well-maintained setups.
Water Temperature
23 - 27 °C
pH Value
5.5 - 7
Water type
Freshwater
Tank level
Middle
Adult size
4.5 cm
Minimum tank volume
>= 50 L
Minimum group
>= 6
GH
2 - 10 dGH
KH
1 - 5 dKH
TDS
40 - 200 ppm
Conductivity
63 - 313 uS/cm
Species description
Geographical Origin and Habitat: This species is native to South America, specifically found in the upper Amazon River basin, notably the Solimões River basin. It inhabits slow-moving forest streams, or igarapés, with dark, acidic blackwater stained with tannins, dense canopy cover, and leaf litter.
Taxonomy and Morphology: Classified within the family Characidae under the genus Hyphessobrycon. It features a laterally compressed, slender body shape typical of dwarf tetras. Adults reach a small size, usually around 2 to 3 centimeters in length.
Social Behavior: A peaceful, schooling species that should be kept in groups of at least 6 to 8 individuals. Keeping them in a proper group helps reduce stress and encourages natural behaviors and vibrant color displays.
Coloration and Sexual Dimorphism: Exhibits a warm golden-brown to reddish body color with a dark lateral stripe running along the lower half of the body. Spawning fins show hints of red and black. Males are slimmer and more colorful than females.
Care, breeding and tankmates
Aquarium Setup: A tank of at least 60 liters is required. Use dense plantings, driftwood, and dried leaves (like Catappa) to create shaded areas and leach beneficial tannins. Keep the substrate dark to make their colors stand out.
Diet and Feeding: Omnivorous. In the aquarium, they accept high-quality micro-pellets, crushed flakes, baby brine shrimp, daphnia, and small frozen foods. A varied diet is essential to maintain their rich color.
Water Quality: Requires soft, acidic water conditions: temperature of 22.0 to 28.0 °C, pH range of 5.0 to 6.8, and hardness between 1 and 8 dGH. Avoid strong water currents as they prefer calm waters.
Compatibility and Cohabitation: Excellent choice for peaceful community tanks. Suitable companions include other small tetras, Corydoras catfish, dwarf cichlids, and peaceful invertebrates. Do not keep with large, predatory tankmates.
Aquarium Breeding: Oviparous. Can be bred in a separate spawning tank filled with fine-leaved plants or spawning mops. Remove parents immediately after egg deposition, as they will consume their own eggs and fry.
Risks and Diseases: Highly sensitive to rapid changes in water parameters and high levels of ammonia or nitrate. Susceptible to common freshwater diseases such as Ich and fin rot under poor water quality.
Geographic Origin and Distribution
This species is native to South America, specifically found in the upper Amazon River basin, notably the Solimões River basin. It inhabits slow-moving forest streams, or igarapés, with dark, acidic blackwater stained with tannins, dense canopy cover, and leaf litter.
Origin
Amazon, Orinoco, and Guianas
Fish profile
- Temperament
- Peaceful
- The temperament of Hyphessobrycon weitzmanorum 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 weitzmanorum 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 well-managed freshwater aquarium, Hyphessobrycon weitzmanorum has an estimated lifespan of between three and five years, although specimens kept in optimal conditions can sometimes reach six years of age. To guarantee its maximum longevity in captivity, it is essential to set up an appropriate biotope with very soft, acidic water with a pH between 5.5 and 6.5 and a stable temperature between 23 and 27 degrees Celsius. Being a shy and gregarious species, it needs to be kept in a group of at least six or eight specimens in order to feel safe and avoid chronic stress, the main cause of diseases. The presence of floating plants, wood, and dry leaves on the bottom helps recreate the shaded areas typical of its natural habitat. A high-quality diet, consisting of microgranule food alternated with live or frozen prey such as brine shrimp nauplii, bloodworms, and daphnia, supports its overall physiological well-being.
- Adult size
- 4.5 cm
- This profile records an adult size of 4.5 cm. Use it to size the permanent habitat and choose compatible furnishings and cohabitants.
- Sex ratio
- Solitary
- While Hyphessobrycon weitzmanorum 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 weitzmanorum 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 weitzmanorum 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 weitzmanorum 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 weitzmanorum 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 weitzmanorum 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 weitzmanorum 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
- In the aquarium, Hyphessobrycon weitzmanorum 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.
Related species
Recommendations grouped by close relatives, companion choices, and similar care.
