I had 5 Elephant noses in a 6ft tank with plecos of varying types, Clown loaches, Dwarf Gourami's, Danio's, Rummynose Tetras, Bronze Corys, Red Tailed Shark, Hoplo catfish.
They can go with lots of different, and were very social, even to the point of ganging up on the red tail shark when it was trying to pick fights with the smallest Elephant nose.