Stocking question-12 gallons

12g might not be enough for two, since they grow to 3" and can be territorial with one another. Quite honestly, I wouldn't even have one in there unless it was kept in thriving conditions.
 
He seems to be doing just fine; he's very active.
 
http://www.loaches.com/articles/hillstream-loaches-the-specialists-at-life-in-the-fast-lane


I found this article describing how to set up a river tank. There's likely lots of info on this site about hillstream loaches. I'm sure most people don't keep their loaches in this type of tank, just thought it was interesting.
I've done that before.:) It was amazing how hillies love to roam around the tank with powerful currents and oxygen maximized for their needs.
 
1 more loach would not hurt,but be prepared to upgrade your tank as the loaches grow,2more tetras would be over kill.
 
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