i put some feeder fish in, between 9 they are 3 baby feeders that are no more than a bite. there is 3 in there they haven't touched. i took them out for a while and put them back it later hoping the piranhas would eat them when i drop them in a second time but no luck. i put in some other foods, like chick, groundbeef, mcdonalds which they usually like ( i bought them off a friend) but ever since i moved them to my place they dont eat. when i drop in food they might nibble at it, but once it hits the bottome of the tank they dont even look at it. i dont know what to do. their mouths are opening and closing like they are hungry but when i feed them they do not eat. one thing i don do it leave food in the tank, except feeders. help please?