I took care of a batch at my old job. Very hard to find info on them. From my experience they are very similar in needs to other morymyrids--fish from Africa with a weak electrical current used to locate food and some have some extensions around the mouth, like the most popular of the bunch, the elephant nose, Gnathonemus petersii, who I've found to have very similar care requirements.
Here would be my suggestions: clean water with a decent current. Very sensitive to water quality. Substrate should be sand so they can dig around without worrying about injury. Diet is mostly worms--blood or blackworms will work. It can be difficult to wean new specimens on frozen worms. I got my elephant noses on hikari carnivore after a while but they had a pretty difficult time eating it due to their mouth shape.
That brings up another important point--make sure they are not outcompeted for food. I would make sure they are good and settled in the tank and eating well before adding anything that could possibly outcompete them. Make sure you have a tightly covered aquarium because they are prone to jumping.
Be careful when keeping with other fish with an electrical current--knifefish, other morymrids, etc. Ive found either keep a group of fish, or one, never two or three as they seem to single out individuals when their numbers are too low.
They are scaleless and very sensitive to medication. Very intelligent fish, they can eventually be trained to hand feed and have some interesting behavior.
Make sure you provide some cave like structures for hiding--PVC pipe works well.
That's all I've got for now, let me know if you have other questions. I might not see this thread so PM me.