Clasoides Rainbowfish

Melanotaenia clasoides is native to the Aru Islands of eastern Indonesia, an archipelago with extraordinary biodiversity. This species has a distinctly deep-bodied, high-arched profile compared to more slender congeners, giving large males a particularly imposing and impressive appearance. The body is covered in large, iridescent scales that flash brilliant silver-blue and green, overlaid with red and orange pigment along the scale edges in dominant males.

Being rarely exported, M. clasoides is a prized find for rainbowfish enthusiasts and collectors. It requires clean, slightly alkaline, moderately hard water typical of its island river habitat. Like other deep-bodied rainbowfish, it is best displayed against dense, dark planting that allows its iridescent colouration to stand out fully.

Melanotaenia clasoides breeds in the standard rainbowfish manner and is not reported to be significantly more difficult than other Melanotaenia species. Hobbyist breeders who have worked with this species note that males develop their most impressive colouration after 18–24 months of growth.

Water: pH 7.0–8.0, temperature 23–28°C, moderately hard; high water quality essential. Tank: Minimum 150 L; dark substrate and background plants to contrast iridescent colouration. Feeding: Quality flake and pellets; supplement with live daphnia, brine shrimp, and occasional bloodworms. Breeding: Standard rainbowfish egg-scattering on plants or mops; colour in males peaks at 18–24 months. Compatibility: Peaceful with other medium rainbowfish; avoid nippy species.