I only had one clown loach (about 2 inches max) and he partnered up with my Silver Shark (about 4 inches and used to swim everywhere together, and the clown used to mimic the silver shark,
the pair of them would swim towards the edge of the glass, and then swim up and down in a syncronised motion, that was quite amusing
Now ive added another loach (about 3inches max) them two now hang around together, they live under my filter when seeking refuge, but do come out to play a lot
The silver shark has now sought a new friendship with the angel fish
I have two polka dot loaches in another tank, and im considering putting them in with the clown loaches tank, and possibly getting one more clown loach
On the subject of moving clown loaches, I moved mine into their new tank, and they have been fine, i moved the tank with the water in it, put the new tank in place, moved some of the old water into the new tank with the filters from the old tank, topped up, left it overnight with just 2 guppies in, then moved the clowns (they were absolute bu66ers to catch) and I just netted them over (i idid put new water from the new tank into the old tank to acclimatise them 1st
They are great fish to watch, along with the polka dot loaches (which dont grow anywhere near as big as clowns)
S