[Delphinus]

I need more information before I can really give you a detailed opinion on what's going on. Is the anemone still inflated? Is the problem just that it is moving around? Can you post a picture?

I'll try to give you a generalized overview though in the meantime. First of all, anemones bought at the stores, invariably those bought in our stores over here at any rate, are recently wild-collected specimens. They're stressed. It is going to take months to get over that stress, and that is if they are going to get over it in the first place.

Secondly, what it takes to successfully house an anemone is a combination of water movement, substrate, lighting, feeding, and suitable tankmates (and of course overall water quality). Although there are some obvious generalities that apply to all species, each species does has its own unique requirements. If just one of these items is not right, the animal will be stressed and thus prone to wandering. A nonstressed anemone has no reason to move. But if it's moving, it means it's looking for something it's not currently getting.

Entacmaea quadricolor (your BTA) looks for a hard substrate but requires to be in a crevasse or a cave or under an overhang. They want their tentacles out in the open light and open current, but they want their pedal disk protected and not exposed. Generally speaking a lot of current is recommended. Lighting needs to be appropriate as well, but I see you're keeping SPS so I assume you have adequate lighting.

Are you feeding the anemone yet? If so, how often and how much and with what? Is the food staying down?