Porthole Rasbora

Rasbora cephalotaenia (sometimes placed in Trigonopoma) inhabits slow-moving forest streams and peat swamps in Borneo and Sumatra. Its common name refers to the series of large, roughly oval dark blotches along the mid-body flanks that give it an unmistakable appearance unlike most other rasboras. It prefers soft, slightly acidic water and a well-planted, dimly lit setup that mimics its natural blackwater environment.

Water: 22–28°C, pH 6.0–7.5, soft to moderate (GH 4–12); slightly acidic water preferred. Tank: 100 L minimum; heavily planted with driftwood; dark substrate and subdued lighting. Feeding: Omnivore; flake, micro-pellets, and frozen/live small invertebrate foods. Behaviour: Peaceful active schooler; keep in groups of 6+; slightly shy but confident in groups. Compatibility: Ideal with other soft-water community species; small tetras, small rasboras, and corydoras.