Senegal Bicher? Rocket Gars?

I recently purchase a 4 inch senegal Bicher and three Rocket gars that are all around 4 inches. Its almost been a week now, and they wont eat anything i give them. I have a couple of healthy feeder fish already in the tank with the gar and bicher but it seems that these predatory fish are not interested. So yesterday i went and bought some small meal worms to feed them. Since the gars and bichers are still pretty young, i bought small meal worms that can fit into their mouths, but when i put the meal worms in, and it floats on the surface of the water, the gar and bichers ignore them and my masheer endded up eating the worms. (i have a couple of the masheer not much bigger than the gars and bichers at around 5 - 6 inches and they seem to school with the small feeder fish) the aquarium they are in is pretty big around 180 gallon. The water quality is good, no build up of nitrates, nitrites etc. What could be the problem? how can i induce the fish to eat? The current tank mates of my new fish are 4 masheer around 5 - 6 inches, 2 parrot cichlid around 4 inches, and one red tilapia around 5 inches and a whiptail catfish around 5 inches. All the fish in the aquarium are eating except for my new bicher and rocket gar.