Ahhh, the ropefish (Erpetoichthys calabaricus).... One of my personal favorites. I have never kept one but I definitely will one day.
The ropefish likes medium to hard water, 72-82 degrees, small amount of salt is good, eats, bloodworms, chopped shrimp, some pre-made foods and small feeder guppies. They like live food but can be trained to accept frozen. you need a large tank (55 gallon minimum) as these guys can grow rather long at 15-30 inches. Tank MUST have a tight fitting lid as they loooove to explore. They have lungs so, they are very well equipped to explore land for more waterholes but will die if no other watersource is found.
These guys will get along with any docile fish that cannot fit in their mouths. They like to be kept in groups of 2-3 or more and will congregate together. Also, provide plenty of hiding spots for them. During the day, they often us them and emerge at night to forage for food.
All in all, the most imprtant things to remember about them is that yo should not keep them with fish small enough to fit in their mouths. Anything larger than that can be considered safe from harm. The other is keeping the tank covered VERY WELL.
Good luck and I hope this helps!