Borneo Sucker

The Borneo Sucker (Gastromyzon spp.), also known as a Borneo Hillstream Loach, is a fascinating bottom-dwelling fish adapted to fast-flowing mountain streams. Its flattened body and specialised fins allow it to cling tightly to rocks and glass while grazing on algae and biofilm. Because several Gastromyzon species are sold under the name “Borneo Sucker,” exact colouration and adult size can vary.

• Adult size: Approximately 4–6 cm, depending on species

• Temperament: Peaceful, although minor territorial behaviour can occur between individuals

• Social behaviour: Social and best kept in a group. Aim for at least 3–5 individuals where tank size allows

• Tank mates: Best with peaceful species that also tolerate cooler, highly oxygenated water, such as White Cloud Mountain Minnows, small danios and other suitable hillstream species

• Avoid with: Aggressive fish, warm-water species and slow-moving fish that require calm water

• Recommended temperature: Approximately 20–25°C

• Recommended pH: Around 6.0–7.5

• Water hardness: Soft to moderately hard

• Minimum tank size: Around 60–75 L for a small group, with a long tank footprint preferred

• Tank setup: Requires strong water flow, very high oxygenation and excellent water quality. Smooth river stones, pebbles and rock surfaces are ideal and provide important grazing areas

• Diet: Primarily an algae and biofilm grazer. Provide naturally grown biofilm and algae alongside spirulina foods, algae wafers and blanched vegetables, with occasional small frozen foods

• Care level: Intermediate

• Swimming level: Primarily bottom-dwelling and spends much of its time attached to rocks, glass and other surfaces

• Special note: A mature aquarium with established algae and biofilm is extremely important. Borneo Suckers should not be treated simply as an “algae cleaner,” as they can lose condition if there is not enough natural grazing available.

Borneo Suckers are social fish rather than schooling fish. They do not swim together in a tight school, but generally benefit from being kept with others of their kind. Their most important requirements are cool, oxygen-rich water, strong current and plenty of mature rock surfaces covered in biofilm.

Live fish are sold subject to availability and may vary slightly in size, pattern and colouration. Please review our livestock shipping and DOA guarantee before ordering.