Anemones are like any other living creature (keep in mind they are not a coral but more like an animal) in that they will not eat for one of two reasons (there are more, but only in rare circumstances).
1. They are not hungry, ie: they do not require any external nutrition. Common actually. We think that they require nutrition when in actuatilaty, they are just fine. Unlike many humans, they will not eat if they don't need the nutrition (sorry.....doctor soap box)
2. They are sick/injured and/or dying. To evaluate this, take a look at it. What is it's color? Bleached white or more "natural" looking? White for any anemone is bad. They are photosynthetic organisms by nature and use solid "food" to supplement their diet. If it is sick and/or dying, then in my experience it is a long shot to get it back to health. PRISTNE water quality is key. More info on your tank and the anemone in question would help.
Many (actually most) anemones do just fine with only good lighting and no supplemental feedings. The most common mistake is to try and feed the anemone when it does not need anthing. When that happens, it usually will spit it out later (usually at night) and the food morsel will either be eaten by other inhabitants or will hide and rot....throwing off your water chemistry.
So, to sum things up, you need:
1. PRISTINE water (aka: ZERO nitrates, nitrites, ammonia; pH ~8.2, dKH ~10, and acceptable Ca as they are not high Ca organixms)
2. Good lighting. LTA's are known for surviving under sub-intense lighting (aka halides) and sounds like you have enough....pending your tank is less than 75 gal.
Again, more info would help.
Hope this helps some.
