I have 15 small clown loaches. They are between 3 and 4 inches long.
When they get to about 6" I plan on building two 450g indoor ponds and linking them together with a water bridge. My clown loaches love the water bridges I have hooked up right now for them on a 90g, 33g, and 6g tanks. They sure do love to explore and go from tank to tank. I just use pvc to link the tanks together.
I like the 2 pond idea because I think it would be necessary for maintenance and quarantines.