Sirajo Goby

Sicydium plumieri is a fascinating amphidromous goby native to the islands of the Caribbean and the Atlantic coast of Central America, including Puerto Rico, the Lesser Antilles, and Trinidad. Like other Sicydium, it uses a fused pelvic suction disc to cling to rock surfaces in fast-flowing streams, and post-larval juveniles migrate upstream from the ocean in large numbers — a phenomenon that has supported traditional net fisheries in some islands. Males in peak condition are attractively marked with iridescent blue-green lateral stripes and flag-like dorsal fins, while females remain cryptically brown. It is a strict aufwuchs grazer requiring a mature biofilm to survive. Water must be pristine, cool to warm-tropical, and highly oxygenated. A species for the patient, experienced amphidromous specialist.

Water: 22–26 °C, pH 7.0–7.8, GH 5–15, KH 3–10; very high dissolved oxygen; zero tolerance for ammonia or nitrite. Tank: 80 L minimum; natural cobble and bedrock layout; mature algae biofilm on all rock surfaces; strong directional flow. Feeding: Strict aufwuchs grazer; spirulina wafers, Repashy gel foods, blanched courgette; will not thrive on protein-based diets. Breeding: Amphidromous; larvae are marine; not achievable in standard aquaria. Compatibility: Peaceful; best with other hillstream species; avoid competitive or fast-feeding tankmates.