Adonis Tetra (Lepidarchus adonis)

The Adonis Tetra (Lepidarchus adonis) is one of the smallest tetras in the hobby, originating from slow-moving forest streams and swampy habitats in Ghana and Sierra Leone, West Africa. Despite its minute size — adults rarely exceed 2 cm — it possesses remarkable delicacy, with a near-transparent body overlaid with gold flecks and black lateral markings that shimmer under subdued aquarium lighting.

This species belongs to the family Distichodontidae, a group largely uncommon in the aquarium trade, which makes the Adonis Tetra a prized find for nano tank enthusiasts. Its natural blackwater environment is characterised by extremely soft, acidic water stained with tannins from decomposing leaf litter. Replicating these conditions in captivity — soft water, low pH, gentle flow, and dim lighting — is essential for the fish to feel secure and display its best coloration.

Adonis Tetras are peaceful micro-predators that accept very fine live and frozen foods such as baby brine shrimp, Daphnia, micro worms, and high-quality micro pellets. Due to their tiny mouths, standard flake food is often too large and should be crushed before offering. They are best housed with similarly sized, non-aggressive species in a species-dominant or nano community setup.

Grouping of at least six individuals is strongly recommended, as these fish feel most secure and exhibit natural schooling behaviour in larger numbers. In a well-planted, tannin-rich aquarium with leaf litter and driftwood, the Adonis Tetra is a jewel that rewards attentive aquarists with graceful, energetic displays.

Tank Setup: A nano aquarium of 30–40 litres is sufficient for a group of six Adonis Tetras. Use a dark, fine-grained substrate and dense plantings of small-leaved species like Java moss, Pellia, or Riccia. Add dried Indian almond leaves and a piece of driftwood to release tannins and soften the water naturally. Ensure very gentle filtration — a sponge filter is ideal — as this species comes from near-stagnant waters.

Water Parameters: Temperature 24–28°C; pH 5.5–7.0; GH 1–8 °dH; KH 1–4 °dH. Soft, acidic water is strongly preferred. Perform 20–25% water changes weekly, using RO water or rain water softened to the appropriate hardness if your tap water is hard.

Feeding: Feed twice daily with micro-sized foods: baby brine shrimp (live or frozen), micro worms, Daphnia, powdered spirulina, and crushed micro pellets. Variety is important for long-term health and colouration. Adonis Tetras will not compete well for food with larger tank mates.

Tank Mates: Keep exclusively with similarly tiny, peaceful species — other micro tetras, pygmy corydoras, small rasboras, and dwarf shrimp (they may prey on shrimplets). Avoid any fish larger than 3–4 cm that could intimidate or eat them.

Behaviour: Peaceful schooling fish; keep in groups of 6+. Males may display to females with fin flaring, but no aggression is directed at other species. They occupy mid and upper water levels.

Health: Adonis Tetras are sensitive to poor water quality and temperature swings. Consistent parameters, pristine water, and a stress-free environment prevent most common diseases. Quarantine all new arrivals before adding to the display tank.