Tucano Tetra

Tucanoichthys tucano is one of the most extraordinary micro-tetras in existence, described from the Rio Uaupés in the Brazilian Amazon. This fish is not merely small — it is among the smallest characins known, with a body so tiny and transparent that its internal anatomy is partially visible. The caudal peduncle carries a vivid orange-red blotch that provides its only obvious field-mark.

Keeping this species demands the most extreme blackwater conditions: ultra-soft water with pH between 4.0 and 5.5, very warm temperatures, and tannins so concentrated that the water appears almost black. Any deviation from these parameters causes rapid stress and decline. This species is suitable only for specialists who have already successfully maintained other ultra-soft blackwater micro-tetras.

Feeding is challenging: only the finest micro-foods are appropriate, including paramecia cultures, the smallest baby brine shrimp nauplii, and specialist nano powdered foods. This is a species maintained as a serious hobbyist challenge and a conservation statement.

Water: 26–30°C, pH 4.0–5.5, ultra-soft (GH 0–2, KH 0–1); blackwater essential. Tank: 30 L minimum; species-only or near-species; zero flow, botanicals, extremely dim lighting. Feeding: Paramecia, infusoria, micro-powdered food, and finest baby brine shrimp nauplii only. Breeding: Extremely rare in captivity; requires absolute replication of natural blackwater conditions. Compatibility: Species-only or with equally tiny, ultra-soft water micro-tetras only.