I think T1 hit the nail on the head, check every parameter of the water, I suspect that it is either water quality or settling in time.....get the water right and fish normally eat.
I am also glad that Sam chimed in about the blood worm, until a few years ago it was used as a conditioning and breeding aid, I am a fan but I do not use it too often. Balance is the key....Steak is nice and probably good for you as long as you do not eat it every day.
Good Luck and I hope it continues to feed