Brown Rhinogobius Goby

Rhinogobius brunneus is the archetypal small stream goby of East Asia, found across Japan, Korea, China, and Taiwan in a wide variety of stream habitats from fast mountain torrents to slower lowland rivers. It is one of the most variable species in the genus, with regional populations differing in colour intensity. Males typically display earthy brown mottling on the body, vivid orange-red dots on the cheeks and throat, and blue iridescence on the gill covers. The species is notably cold-tolerant, thriving in unheated aquariums in temperate European homes through winter. It is a prolific cave spawner in captivity, with the male guarding the adhesive eggs until hatching. The amphidromous larvae drift downstream in nature, but some aquarists have succeeded in rearing them using a salt-water transition approach.

Water: 15–24 °C, pH 6.8–7.8, GH 4–18, KH 2–12; tolerates a wide range; no heating needed in temperate climates. Tank: 60 L minimum; river pebble with flat stones and ceramic caves; moderate to brisk flow. Feeding: Carnivore; enthusiastically accepts frozen bloodworm, daphnia, and brine shrimp; also takes small pellets. Breeding: Reliable cave spawner in captivity; male vigorously guards egg clutch; amphidromous larvae are challenging to raise. Compatibility: Generally peaceful; may be kept with cool-water danionids, loaches, or hillstream species.