Borneo Sucker

About

A compact hillstream loach from Borneo, Gastromyzon stellatus is native to the fast-flowing, oxygen-rich rocky streams of the Sadong and Lupar River basins in Sarawak, Malaysia. Its dark brown body is peppered with numerous small yellow spots and blotches. A pattern that helps distinguish it from close relatives like G. zebrinus and G. crenastus, though the three can overlap enough in appearance to make confident identification genuinely tricky, even for experienced keepers. Like all Gastromyzon, it has a flattened body, horizontally oriented paired fins, and fused pelvic fins that together form a powerful suction cup, allowing it to grip smooth rocks in strong current. It effectively crawls rather than swims, spending most of its time grazing biofilm and algae from hard surfaces. Despite the 'aggressive' and 'territorial' tags, conflicts are mostly low-level squabbles over prime feeding real estate rather than serious aggression. Keeping a group of four or more actually tends to spread this behavior out and makes the fish far more interesting to watch. Tankmates should be chosen carefully: smaller, similarly active species that won't outcompete or intimidate them work best. It regularly appears in the trade under catch-all labels like 'Borneo sucker' or 'butterfly loach', often mixed in with other Gastromyzon species, so inspect shipments closely if accurate identification matters to you.