Speciosa Hillstream Loach

Sewellia speciosa inhabits the fast-flowing, clear, oxygen-saturated rivers of central Vietnam. Its name reflects the species' particularly attractive spotted pattern — rows of pale ocelli on a dark warm-brown ground create an appearance reminiscent of a fine textile. Its body is even more dorsoventrally compressed than most hillstream loaches, maximising the suction effect of its modified fin surfaces.

In the aquarium, S. speciosa is an active and rewarding species when water quality and current are maintained at the required levels. Like its congeners, it spends the majority of its time on flat rock surfaces, grazing methodically. It is sensitive to heat and will begin displaying respiratory stress above 25 °C; a chiller is advisable in warm climates.

This species benefits significantly from the presence of established biofilm on décor — setting up the tank several weeks before introducing the fish and seeding rocks from a mature aquarium will help provide the microalgae community on which the species thrives.

Water: 18–24°C, pH 6.5–7.5, GH 4–15, KH 2–8; dissolved oxygen must remain near saturation — use a powerful circulation pump or spray bar. Tank: 80 L minimum; smooth river-worn stones, slate, and aged wood to develop biofilm; good mechanical filtration to remove suspended detritus. Feeding: Grazes biofilm; supplement with spirulina wafers, algae tabs, and blanched courgette or cucumber. Breeding: Egg-scatterer spawning under rocks; condition with cooler water and increased flow; fry require established biofilm and infusoria. Compatibility: Peaceful community species; compatible with cool-water dither fish such as danios or mountain minnows.