Hillstream loach

Behaviour and habits

The hillstream loach is a flattened, stream-dwelling fish that clings to rocks in a current, feeding on the algae and biofilm that coat the surfaces. It behaves quite unlike a still-water tropical fish: it needs cool, fast, oxygen-rich water and will spend its time glued to stone, wood or glass. It is peaceful and does best in a small group in a stream-style setup with a strong pump.

What to feed, and how often

It grazes aufwuchs — the algae and tiny organisms on surfaces — and needs these to thrive, so add it to a mature tank with plenty of grazing area. Supplement with algae wafers and blanched vegetables, and feed daily, as a grazing fish can otherwise slowly starve in a spotless tank.

Water changes and maintenance

Change about 25% weekly and, above all, keep a strong current and high oxygen. These conditions are not optional for this species — in warm, still, low-oxygen water it simply fails, no matter how clean the water is.

Care and how easy it is

Not a still-water fish: it needs flow and oxygen, which makes it a specialist choice rather than a general community fish. A stream-style setup with a powerhead and cool water suits it best.

Common health problems

Sensitive to warm, low-oxygen water; otherwise hardy.

If it gets sick

Fix the temperature and flow before reaching for medicine — most hillstream-loach problems are environmental, not infectious.