Cobalt Stiphodon Goby

Stiphodon elegans is one of the most brilliantly coloured freshwater gobies in the world. Males display an intense electric-blue body suffused with vivid orange across the head and flanks, rivalling any marine species. Females are more cryptically brown with subtle spotting. Native to fast-flowing, crystal-clear mountain streams in the Philippines and Ryukyu Islands, this amphidromous species migrates between freshwater and the sea during its larval stage. In the aquarium it requires excellent water quality, high oxygenation, and a mature biofilm of algae and diatoms on which to graze. Males will spar with conspecifics but rarely cause injury, and the visual display alone makes the occasional skirmish worthwhile for dedicated nano goby enthusiasts.

Water: 22–26 °C, pH 7.0–7.8, GH 5–15, KH 3–10; high dissolved oxygen essential — use powerhead or spray bar. Tank: 60 L minimum; smooth river pebbles, flat stones, and mature algae-covered surfaces; avoid silt or fine sand substrate. Feeding: Grazes biofilm; supplement with spirulina wafers, blanched spinach, and Repashy Soilent Green; rarely accepts meaty foods. Breeding: Females deposit eggs under stones; larvae are marine and rarely raised in captivity; not a practical breeding project. Compatibility: Keep with other peaceful hillstream species; avoid boisterous or fast-feeding fish that outcompete for biofilm.