I have had zero issues wiith them getting along with Leopard Bush Fish, Otto's, Cardinal Tetras, Boesemani Rainbows, Roseline Sharks, Plecos, Clown Loaches, Ember Tetras, African Dwarf Frogs, and ropefish.
I have read that they will not tolerate any other rainbow, red-tail or black shark though.
They will also get territorial as they mature and will claim an area, usually like a cave or other hiding place. I have seen him claim stuff in my tank, although it is planted along with a lot of driftwood, so everyone seems to have their own place. No issues so far.
~30 Rummy-nose Tetras, ~30 Balloon Lamp-eye Tetras, 2 Bristlenose Plecos, 4 German Blue Rams, 1 Rainbow Shark ~15 Amano Shrimp, 8 Roseline Sharks, 3 Clown Loaches, 2 SAEs