I haven't kept them in years, but they are much like robertsoni, rostratus, and similar sand sifters.......i.e. not terribly aggressive.
I always had the best success keeping them in groups of five or more (or by themselves). Provided the tank is very large, they seem to appreciate a social order, and you generally get one dominant male that runs the show but without too much aggression. The fewer fish you keep, the more squabbles can get serious.
Make sure their tank has sand as a substrate, not gravel. They need to be able to sift the sand through their gills, rather than having to spit it back out. If they can do that, they seem to be much more comfortable.
It's interesting you brought them up. I just about pulled the trigger on a group of large specimens at my LFS about two hours ago! You certainly don't see them often, mush less a group of fully grown adults!