In general anemone need relatively high light. In the 300 - 400+ PAR range is good (this is equivalent to SPS lighting levels).
Total lighting hours also need to be factored in, else too long hours even at lower light levels can cause bleaching.
Anemone can survive in 150+ PAR range (eg sand bed) but the bubble tips won't be so nice. They will look amazing in higher light.
Other signs of a stressed anemone - wont eat, won't attach to rock or keeps moving to a dark place to hide in the dark.