Carpet anemone not doing well

[syncro]

Thanks for all the replies.

Today it is expelling wisps of brown fluid the consistency of syrup - partially digested food? Equivalent of vomit/diarrhea? It was doing this when I was feeding more heavily. It is still eating and foot has remained buried in the sand. However, not very sticky anymore and slower to respond to poking. This is a haddoni (no spots/stripes on the underside).

Ideas:
More food: Already tried up to the equivalent of a silverside every other day. Did not slow decline. Intuitively, the current behavior doesn't seem like under-feeding but it isn't a human.
Flow: Ok, moved the MP10 closer and one notch faster.
Irritation: There were bristle worms and brittle stars, so irritation was possible. Removed these along with RBTA yesterday.
Water quality: Possibly still have chemicals from RBTA. Possibly sick carpet is contaminating the water. Any other tests I can/should run?
Lighting too high: 250w MH on for 9 hrs, T5s on for 11 hrs. Too much light? Acclimated to this level over 9 days. Too fast?

Today:
- changed out the carbon
- 12% water change