Encyclopaedia
January tetra
Hemigrammus hyanuary
An elegant but underrated Amazonian tetra: a yellow-green iridescent stripe runs along the body from snout to caudal peduncle, above a thin black band — creating a unique natural light effect. Named after Lake Hyanuary near Manaus where it was discovered. The eye iris is bright green, a distinctive detail. Peculiarity: wild specimens sometimes show a golden sheen caused by a parasite in the natural biotope, absent in captive-bred specimens. Ideal for dark-water Amazonian biotopes with leaves, driftwood and tannins.
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22 - 27 °C
6 - 7.5
Freshwater
Surface and middle
4 cm
>= 40 L
>= 6
2 - 12 dGH
1 - 6 dKH
40 - 240 ppm
63 - 375 uS/cm
Species description
Care, breeding and tankmates
Geographic Origin and Distribution
Origin
Fish profile
- Temperament
- Peaceful
- Diet
- Omnivore
- Sex ratio
- School
- Feeding frequency
- Twice daily
- Bioload
- Low
- Flow
- Strong
- Jump risk
- No
- Reproduction
- Oviparous
- Compatibility & tankmates
- Peaceful
- Tank level
- Top/Middle
Window to the official scientific data of the species
Scientific Parameters & Models
- Trophic level
- 3.2 ± 0.4 se
- Resilience
- High (less than 15 months)
- Phylogenetic uniqueness (PD50)
- 0.5
- Bayesian Length-Weight
- a = 0.01259, b = 3.05
Image gallery
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Related species
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Variants and close relatives
Same atlas type, nearby scientific identity, genus, or family.
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Similar care
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