It depends on what kind of africans you keep. If you have mbuna then I wouldnt add an eel in there, their diets are too different. Most of the time you'll have to hand-feed your eel worm-type food. Either live earthworms or frozen blood worms.African cichlids are much more vigarious feeders than most fish and they'll most likely eat the food before your eel will even know it's there. If you have mbuna that have sensitivity to malawi bloat, the protein from the blood worms could cause an epidemic.