You will see the fish I have in my 10g and the x-ray tetras don't ever eat the flake food I offer them but the red eyed tetras gobble it up. The x-rays will just stay at the bottom motionless while the other fish are getting the food. But the x-ray tetras seem to like and eat the corys food which is sinking wafers and they seem to get at most of it before the corys have a chance even though I split the wafer into three parts and spread it out through the tank. Why are they refusing the flake food?