Did you try soaking them in garlic juice. It could just be that he needs some time or perhaps there is another underlying issue that's causing a lack of appetite.
Right now, for some reason (even though he's been in the same tank since November), my male is terrified to be out in the open, so he hasn't been eating much. He'll dart out and grab a pellet and dart back to his hiding place. If he happens to miss the pellet in his frantic darting, he'll just not eat that time. But he's also dealing with a swim bladder issue, so it's possible that his difficulty swimming makes him feel vulnerable, so he'd rather not eat if it means exposing himself to possible danger.