My newest addition to my community of fish was a Black Ghost Knife Fish! His name was Fin and wasn't shy at all! He loved swimming in and out amongst all the plants and he loved to swim with all my other little fishes. To feed a BGKF you need to have Frozen Bloodworms, take a small chunk and hold it in the water near him/her. Once you see them rise to your hand to check out the food, If you can tell they're eating you'll see them almost vacuuming the worms.
Unfortunately, Fin died only a couple of days ago though :( So to have a BGKF you need a MASSIVE tank and im saying right into 150 gallons and MORE! so before you go out and buy one, make sure you have all the necessities for it :)
^^ My BGKF Fin :) ^^