Origin and Appearance

The Poecilocharax weitzmani, commonly called Black Darter Tetra or Black Morpho Tetra, hails from blackwater habitats in the upper Amazon and Orinoco basins across Colombia, Venezuela, Brazil, and Peru. These small fish reach 3-4 cm, with males displaying intensified black hues, white-tipped pelvic fins, and territorial flair during breeding, while females darken with red anal fins when ripe. Beginners will appreciate their subtle elegance in a dimly lit tank mimicking shaded forest streams.​

Aquarium Setup

Create a mature biotope with soft sandy substrate, driftwood roots, and leaf litter from beech, oak, or Indian almond leaves to lower pH naturally and provide hiding spots. Add slow-growing plants like Microsorum, Taxiphyllum, or Cryptocoryne that tolerate low light, plus PVC pipes or caves for males to guard eggs. Use gentle air-driven filtration to maintain stability—never add to new tanks, as they demand pristine, soft acidic water (pH 4.5-6.5, <5 dGH, 24-28°C).​​

Feeding and Health

As micropredators, they ignore flakes and need daily live or frozen foods like Daphnia, baby brine shrimp, micro worms, or grindal worms to condition for spawning and avoid hollow-bellied imports. Feed small portions near shy individuals to ensure eating; overactive tankmates stress them, so keep in groups of 5-6 in species-specific setups. Lifespan reaches 3-5 years with stable parameters.​

Breeding Tips

Unique among tetras, males brood eggs in caves without eating, defending them until fry swim free after 2 days—remove adults post-hatch to protect young fed on baby brine shrimp. Condition with rich live foods; success requires ultra-soft water matching nature (pH ~4.5-5).