I have been keeping my African p. annectens for about 6 months now, so I am not the expert that many on the forum are, but I will tell you what has worked for me. I feed mine a varied diet. Black worms, earthworms, beef heart, snails, and now algae wafers and some vegetable matter like small pieces of zucchini. I remove left over food (except black worms) after a couple of hours or when it shows obvious disinterest. The black worms find their way into the gravel and it roots around for them latter. I tried feeding it every day, twice a day but found it became lazy and unenthusiastic and ate smaller and smaller portions, leaving me with a lot of cleaning and food wasting. I now feed it as much as it will eat enthusiastically once a day. If it gets lazy I go every other day if it is gobbling every thing in sight I will offer it another feeding on the same day. I think daily interaction with the fish as well as reading the back posts you find here will go along way in helping you find the “sweet spot” that works for you and your fish. This is what has worked for me, and so far so good.
(lesson learned). My question is, how often and how much do you guys feed yours?? 
