Roseus Danio

Danio roseus is a quietly attractive danio from the Mekong basin of Thailand and Laos. Males develop a soft rosy-pink flush along the lower flanks and into the fins during breeding condition, giving the fish a warm, pastel charm that distinguishes it from more boldly patterned danios. Females are fuller-bodied and slightly paler. In the wild it inhabits slow to moderately flowing streams and rice paddies among dense vegetation. In the aquarium it does best in a blackwater-inspired setup with tannin-stained water, dark substrate, driftwood, and heavy planting to recreate its natural environment. Like all danios it is a peaceful, active schooler. Water quality must remain high as it is more sensitive to ammonia and nitrite than hardier danio species.

Water: Temperature 20–26 °C, pH 6.0–7.5, soft to moderate hardness; tannins beneficial. Tank: 60 L minimum; blackwater setup with driftwood, leaf litter, and dense planting; dark substrate. Feeding: Flake and micro-pellets accepted; enrich diet with frozen daphnia and baby brine shrimp. Breeding: Egg-scatterer over fine plants or mops; slightly acidic, warm water promotes spawning. Compatibility: Peaceful; avoid boisterous or nippy tankmates; pairs well with small tetras, rasboras, and small corydoras.