Keep in mind I've managed to kill one anemone and the one I have now is probably doing about average, but in my great search to find out what I've been doing wrong (and right), here are a few things I've learned. No one really seems to know why some BTAs will keep their bubble tips and some won't. Someone will buy one at the store with nice big bubble tips, bring it home and they go away. . .and vice versa. From everything I've been told, though, it's not a reflection of the anemone's health, so I wouldn't worry about that. I'm still trying to figure out the whole light thing myself, but I'd guess that you're not doing bad for lighting. You may want to specify how high up in the tank your anemone is, though, so people more experienced than I can help you out there.
As far as what to feed them, silversides seem to be the all time favorite. My LFS never seems to have any in, so I've been feeding mine shrimp and mysis a couple times a week, and that seems to work fairly well. I've also heard of people feeding them krill or even not at all (assuming sufficient lighting). Anyway, best of luck.