As said by cory feeders are not a good source of nutrition and prepared food are better for your bichir.
I have 3 bichirs and none of mine are evr fed feeders, i feed mine on a diet of sinking carnivor pellets, meaty frozen foods like mussels and cockles (shelled) and live foods like earthworms bloodworms and ghost shrimp.
If you have other fish which will get to the food before your bichir then as cory mentioned you will need to place the food as close to the bichirs hiding place as possible, feeding just before lights out will also help if your bichir is reluctant to come out and feed when the lights are on.