lined wrasse, Anampses lineatus, stopped eating


I killed ALL that Coral!
I've had this big guy (5")about 4 months. Been a good active fish, eating well. About a week ago noticed it not swimming as much, and not super interested in eating. Now he swims awhile then lays on the sandbed for awhile, might peck at one or two pieces during feeding. Certainly not active eating.

Just interested in thoughts what might be going on. There are no visual indicators, sore, ick, gasping, torn fins.

Tank is stable and mature 210 sps. No other issues with 20 tank mates.