They really aren't that hard to up-keep, but make sure that your tank does not go through any fluctuations in Ph or Temp (The African Butterfly can be sensitive to fluctuations in aquarium pH and temperature).
The African Butterfly Fish isn't really the fish that will bring movement to the top area of the tank. They seem to float much of the time, so if you're looking for a really active fish this may not be the one for you.
Also Make sure to have a tight fitting lid, they are jumpers!