Yellow Tang not eating

[AxelG]

My Yellow Tang is not eating. His eyes look clear, no white spots or black spots, no red veins and his fins look fine. I feed him a clip of green seaweed every day for browsing and at dinner I feed spirulina enriched brine shrimp.

I'm going to try a clip of spinach soaked in garlic since I saw in some posts that Vitamin C and garlic are recommended. I'm also going to do a water change, even though my water quality is good and I have been doing bi-weekly 10% water changes.

Any suggestions on what else I might try or look for?

Thanks,
AxelG