Zosterophorum Sicyopus Goby

Sicyopus zosterophorum is a rarely imported amphidromous goby endemic to the Philippines, found in fast-flowing, clean mountain streams and riverbeds of cobble and bedrock. Males are among the most brilliantly coloured freshwater gobies available, displaying intense orange to crimson-red body colouration contrasting with metallic blue-green cheek patches and iridescent fin margins. The pelvic fins are fused into a suction disc allowing the fish to cling to vertical rock faces and resist powerful currents. This species is demanding in care: it requires very high water flow, excellent oxygenation, near-pristine water quality, and a mature biofilm for grazing. It does not adapt well to typical community aquarium conditions and is best reserved for experienced hillstream specialists who can provide its exacting needs.

Water: 22–26 °C, pH 7.0–7.8, GH 5–15, KH 3–10; very high dissolved oxygen; intolerant of nitrate above 10 ppm. Tank: 60 L minimum; strong directional flow from powerhead; mature algae and diatom biofilm on rocks essential. Feeding: Obligate biofilm grazer; spirulina wafers and Repashy gel foods; rarely accepts animal-based foods. Breeding: Amphidromous; not captive-bred; larvae require marine conditions. Compatibility: Peaceful; best with other stream gobies or small hillstream loaches; avoid fish that disturb biofilm.