SK01 Pink Tail Borneo Sucker, Gastromyzon sp. SK01, is an undescribed hillstream loach from Borneo, where it inhabits cool, fast-flowing mountain streams with rocky substrates and extremely high oxygen levels. These streams are typically crystal clear and shallow, with strong current flowing over smooth stones, gravel, and submerged rock surfaces coated in biofilm and algae. The species is associated with highly oxygenated river systems in Sabah and surrounding Bornean upland regions. Adult Gastromyzon sp. SK01 typically reaches about 1.5 to 2 inches in length. The body is flattened and highly specialized for life in fast current, with broad pectoral and pelvic fins forming a suction-like surface that allows the fish to cling tightly to rocks. Coloration consists of a dark brown to black base overlaid with lighter mottling and intricate patterning, while the caudal fin and rear portions of the body display vivid pink to reddish coloration that gives the species its common name. The contrast between the dark body and bright pink tail is especially striking under strong lighting and against pale stonework. A tank of at least 20 gallons is recommended for a small group, though larger aquariums provide better long-term stability and grazing area. The aquarium should be designed as a river-style setup with smooth stones, rounded rockwork, and strong directional flow. High oxygenation is essential, and additional circulation pumps are strongly recommended. Fine sand or smooth gravel can be used between rocks, but the majority of the layout should emphasize hard surfaces for grazing. Water conditions are critical to long-term success. Temperatures between 68 and 76 degrees Fahrenheit are ideal, with a pH range of roughly 6.5 to 7.5 and soft to moderately hard water. Clean, highly oxygenated water is absolutely essential, and this species does poorly in stagnant or poorly maintained aquariums. Frequent water changes and strong filtration are important. Feeding SK01 Pink Tail Borneo Suckers requires established grazing surfaces. In nature they feed primarily on biofilm, algae, and microorganisms scraped from rocks. In the aquarium they should be provided with mature surfaces containing natural biofilm and supplemented with algae wafers, spirulina-based foods, Repashy-style gel foods, and finely powdered prepared foods. They are not efficient algae “cleanup fish” in immature aquariums and should not be added to newly established tanks. Temperament is peaceful and social. Gastromyzon sp. SK01 does best in groups and generally ignores other species, though minor territorial displays between individuals may occur over preferred grazing spots. Suitable tankmates include other peaceful hillstream species, small danios, rasboras, and similarly adapted stream fish that tolerate cooler, high-flow conditions. Breeding in captivity is rarely documented for undescribed Gastromyzon forms. Like related hillstream loaches, spawning likely occurs among rock crevices or substrate in high-flow environments, but successful reproduction remains uncommon in home aquariums. Gastromyzon sp. SK01 is a highly specialized and visually striking hillstream loach that thrives in mature, high-flow aquariums with excellent oxygenation and established biofilm. Its vivid pink tail, intricate patterning, and unique clinging behavior make it an exceptional species for dedicated river-style setups.
