There is a African Butterfly Fish girl in my tank for quite some time now, I posted some of my experiences and a few pics over here
http/www.plantedtank.net/forum/viewtopic.php?t=1913 in case anyone is interested.
Very peaceful fish, should only by kept with other tranquil fishies of it's size (I have a pair of pearl gouramies sharing the surface area, and they get along great).
I feed her flies, earwigs, moths, little mosquito fishies, daphnias (live, with some air under their shells they stay at the surface). I think they would take frozen food like mosquito larvae, but definitely prefer something that moves!
I don't agree that they are picky about water conditions, but it would be very cruel to keep the Butterfly together with fast-moving fish like barbs and danios that would bother him all the time.
By the way... mine has never even tried to jump out of the tank. She does jump after flies and the little fishies, as long as they are on the surface. I guess it is like with you getting into a hotel... some you'd rather stay outside. She loves to hang out in the dense vegetation on the surface... between Riccia, Myriophyllum and swords that made it to the surface... until I show up, then she comes out and expects a big fly