Hmm...well, it sounds as if you are feeding it correctly. They like finely minced meaty foods (mysis is great) about once or twice a week. The only thing I wouldn't be too sure about is the garlic. Garlic is fine with fish, but I don't put it in my food mixtures intended for the corals...anybody else have some opinions on this?
Does it still look shrunken, or has it gone back to normal since the 15th? If it looks normal, I would tend to agree with Frederick and say that it was possibly spawning.

Wendy