We have 2 ropefish in one of our tanks with several other fish. There's a Jack Dempsey, peacock cichlids, frontosa, kribensis, crayfish, plecos, convicts, rainbow fish, gudgeons and some snails. They've been together for several months now and we've not had any problems. You will want to make sure the hood of your tank has absolutely no holes that they can escape from. They can live outside of the water for an estimated 4-6 hours but I wouldn't take the chance.
Our ropefish go through periods where they are always out and when they always hide. I guess it's just their nature. Despite being "bottom feeders," ours have also learned to come to the top and eat with the other fish or they're going to miss out. They are really a neat addition to the aquarium. They like their own species for company and will sometimes eat small fish so make sure you don't keep anything else in the tank that will fit in their mouths, just to be safe.