[leebca]

I would suggest you perform a very large water change -- over 60% if you can. Make sure you do this with properly adjusted new water -- see: How to Make a Safe Water Change for Marine Fish

Stop soaking the food in garlic juice and fat supplements. All the food will taste the same to this fish. Give the fish a chance to savor the various flavors as nature intended before trying these additives. Keep offering different foods AND the same foods by different packagers. Give live a try (brine shrimp, mysids (saltwater mysis), tiny black worms, etc.).

Offer foods in different sizes -- starting with what you might consider too small for this fish.

Try to establish a pattern of time and place (within the tank) to feed. Do not touch the food with your hands (unless gloved). Fish have a much better internal 'clock' that we do.