All fish / Gastromyzontidae

Sewellia analis

Sewellia analis

Also known as hillstream loach, butterfly loach, sewellia loach, reticulated hillstream loach, セウェリア, 爬岩鳅

No free-to-use photo of this fish yet. Took one yourself? Send it to us and we will credit you.

This is a small, flattened hillstream loach with fins that spread out like a sucker, letting it cling to rocks in fast water. Its golden brown body is covered in dark spots and blotches. Keepers like it for its odd shape and its habit of grazing algae off stones and glass.

Care at a glance

Care level

Moderate

Temperament

Peaceful

Adult size

5 cm

Temperature

20 to 25 °C

pH

6.5 to 7.5

Smallest tank

80 litres

Keep as

Group of 5 or more

Diet

Omnivore: biofilm and algae, plus sinking algae wafers, frozen bloodworm and daphnia

Swims

Bottom of the tank

Lifespan

5 to 8 years

Water

Freshwater

Wild range

Vietnam (central highland streams)

Breeding

It has bred in well kept aquariums that have strong flow and plenty of rocks, but it does not happen often. The eggs are scattered among the stones and the parents give no care. Raising the fry takes a mature tank with plenty of biofilm.

Good to know

It needs cool, well oxygenated, fast moving water and a mature tank with lots of biofilm, so it should not go into a new setup. It is often confused with Sewellia lineolata and similar species, and trade names are not reliable.