Do hillstreem loaches need fast flowing water?

Question

Do hillstreem loaches need fast flowing water?

Answer 1

Yes, they need flowing water.  May not be fast, but moving at least.  In nature, hillstream loaches usually inhabit rapid flowing, rock stewn streams.  You can duplicate this by having a powerhead in your tank.

The fish have adapted to this environment by having a flat, streamline body and a sucking mouth.  Its mouth is used at rasping algae on rocks, and clinging on to it to prevent the fish from being sweep away by the fast flowing stream water.  They also have modified fins that also help them cling onto the rocks.

Answer 2

Not necessarily fast flowing water, but well oxygenated water.  Some species will need much cooler water, but others will be more tolerant of warm water.