well silversides or lancefish are usually the best food for anemones, mysis will do but it provides less bang for the buck for these animals. They should be fed about once a week or every other week......a lot of anemones perish from overfeeding.....yes that is right overfeeding. You have a really nice healthy looking specimen. Do yourself and your nem a favour and wrap your powerheads in plastic canvas secured with zip ties until she is settled into the spot where she will hopefully stay. My first nem (which was bought without enough research was severly bleached) decided that any place in the front of the tank was bad and promptly hid out in the back in an inaccessible area and eventually perished due to the stress it was under when I got it. I have a gbta now in my 75g that I have had for over a year, it was the size of a quarter when I bought it and it is now about 10-12inches across when expanded.....this one also liked the back side of the rock work though it is in a good spot to feed. I feed it a good sized piece of silverside once a week and it gets what ever mysis etc are floating by. It has also been known to feed on the bangaii babies as the male usually spits the babies within a couple of inches of the nem and I have seen the poor things caught up in the tenticles....c'est la vie......
I have also a lta which I have been nursing back to health....was bleached to a peachy colour when I got it and now it is a dark brown with hints of green and purple to its tips.......nice comeback. It also gets pieces of silversides and it has 2 clarkiis hosting.....who feed it constantly
Do you have clownfish that will host your bta? I have two percs who won't go near it and have no interest what so ever in it...