i have a sewelia lineolata, a relatively small type of hillstream loach, and i keep it in a 10 gallon with filter and 400 gph
powerhead. one side is sand and one side rocks, so the powerhead doesn't blow the sand around and so the loach has something to cling on. this tank sits in direct sunlight, to grow algae to feed the loach. i have a heater that keeps it at 64 degrees. they are pretty easy to care for, as long as you have the right setup and an established tank. i plan on setting up a 33 long, in the next few months, and putting a few different species of hillstream loach into it. this is the setup plan, to optimize flow and oxygen level. the sponge will act as a filter.
they come from cold, fast flowing streams in southeast asia and do best when you replicate their natural environment