What are all the conditions in your tank? Lighting, Nitrates, flow. How old is your tank? How long has the RBTA been in this particular tank? Have you recently changed lighting? How old are you bulbs?
From first glance, I'd guess it might be a flow issue. Although, if it were a flow or lighting issue, usually a BTA would attempt to move to a "happier" place. As long as it's getting enough lighting, I'd suggest stopping the feedings for awhile and see if anything improves. You'd probably have to stop for quite some time, while not making any other changes, to figure out if it's a feeding issue.
The only reason I suggest this is that if an anemone is getting enough light, it really doesn't need to be fed at all. I have a HUGE RBTA and give it incidental feedings about once or twice a month...lol.