Double Blue Zebra Borneo Loach - Gastromyzon sp.

Double Blue Zebra Borneo Loach (Gastromyzon sp.)

The Double Blue Zebra Borneo Loach, Gastromyzon sp., is a specialist Borneo hillstream loach with a flattened sucker-like body, bold zebra-style striping and attractive blue tones through the fins or tail. Also known as a Blue Zebra Borneo Sucker, Zebra Borneo Loach or Bluefin Zebra Hillstream Loach, this peaceful grazing fish is adapted to fast, shallow, oxygen-rich streams. It is best kept in a mature river-style aquarium with strong flow, smooth rocks and natural biofilm, rather than a standard warm community tank.

Common Name:
Double Blue Zebra Borneo Loach, Blue Zebra Borneo Loach, Blue Zebra Borneo Sucker, Bluefin Zebra Hillstream Loach, Zebra Borneo Sucker, Borneo Hillstream Loach.

Scientific Name (Latin):
Gastromyzon sp.
Unidentified trade form; may be confused with related striped or blue-finned species such as Gastromyzon farragus, Gastromyzon aeroides, Gastromyzon ornaticauda or other Bornean Gastromyzon species.

Maximum Size:
Usually around 4–6 cm, depending on the exact species or collection form.

Water Type:
Freshwater

Origin / Natural Habitat:
Borneo. Gastromyzon loaches are native to clear, shallow, fast-flowing streams with rocky substrates, high dissolved oxygen and strong water movement. They use their flattened bodies and specialised fins to cling to smooth stones and graze biofilm, algae and aufwuchs from hard surfaces. Seriously Fish describes Gastromyzon species as obligate inhabitants of swift, shallow, clear, oxygen-saturated streams.

Water Parameters:
Temperature: 20–24°C
pH Range: 6.5–7.5
Hardness or Salinity: Soft to moderately hard freshwater; clean, stable and highly oxygenated water is essential.

Temperament:
Peaceful, but mildly territorial with its own kind over favourite rocks and grazing patches. It is not aggressive towards other fish and is best kept with calm species that enjoy cooler, well-oxygenated water. Avoid large, aggressive or very boisterous tank mates.

Diet:
Biofilm and aufwuchs grazer. Provide mature rock surfaces with natural algae and microbial growth, plus sinking algae wafers, spirulina foods, fine sinking pellets, Repashy-style gel foods, blanched courgette, spinach, cucumber and occasional small frozen foods such as daphnia, cyclops or brineshrimp. Do not expect this species to survive by “cleaning glass” alone.

Minimum Tank Size:
A minimum of 75 litres is recommended for a small group, with 90 litres or more preferred. A long, shallow aquarium with open flow channels and lots of rock surface is much better than a tall, still aquarium.

Behaviour & Activity:
A bottom and rock-surface dwelling loach that spends most of its time attached to smooth stones, glass, wood or broad leaves while grazing. It is best kept in a small group of at least 3–5, provided there is enough surface area and food. Individuals may shuffle, chase or display over preferred stones, but this is usually harmless when the layout has plenty of grazing space.

Aquarium Category:
Community Fish
Suitable for specialist cool-tropical communities with peaceful fish such as White Cloud Mountain Minnows, small danios, Stiphodon gobies in suitable setups, other hillstream loaches, small rheophilic barbs and calm species that enjoy similar flow and oxygen levels. Avoid warm tropical community tanks, aggressive cichlids, large predators, fin-nippers and fish that dislike strong current.

Special Requirements or Care Notes:
This is a specialist hillstream fish, not a general algae eater. Provide mature filtration, strong aeration, added flow, smooth river stones, pebbles, sand or fine gravel, and bright enough lighting to grow natural grazing films. Avoid new aquariums, low-oxygen setups, dirty substrates and prolonged high temperatures. Extra aeration is especially important during warm weather. A secure lid is sensible, as hillstream loaches can climb glass and explore gaps.

Suitable for:
Intermediate fishkeepers

Availability:
Occasional / specialist import / usually wild-caught where relevant

All images are a visual representation of the fish you will receive, made to be as accurate as possible. Please note that Mother Nature is a wonderful thing, and variation in patterns and colours will occur — that is part of the unique beauty of these animals.