About your question to me:
My apologies, for not answering sooner...
Starving and bleached go hand in hand a lot of the time.
A white anemone (BTA) is a bad color, because it means it has lost its little animals who live inside it, which give it color. Those little animals (zooxanthellae) live inside the anemone and they assist it to keep its color and to survive.
They feed on things which free-float in the water and also on foods ingested by your anemone, and thrive off of good lighting. You have good lighting and he will adjust, hopefully.
When a coral or an anemone becomes bleached (white) it is a very bad sign. It means that the little animals who symbiotically live within it are starving to death. Many times, an anemone will expell these little animals as they die and you will actually see its color coming out in its poop.
You didn't know this, of course, when you bought it, and LFS are famous for selling anemone who are bleached and starving to customers, becuase most people tend to buy white rather than brown anemone.
So, making a long answer shorter...lol...the first thing not to do is panic. Do not panic. You did the best thing for that anemone possible by bringing him home to your wonderful lighting, which will assist to feed the little zooxanthellae inside him, and with time, he may adjust just fine.
I don't think anything you did caused anything, from what you have told us, and it sounds like as soon as it begins to adjust to your lighting a bit better, it will be in a much improved atmosphere.
For what it's worth, it's very rewarding to rescue and to revive an anemone who has been through such a tough time.
My suggestion to you is to go against everyone else's suggestions to feed it silversides, and to instead feed it krill. Although a higher fat content, the coloration of the krill filters into the anemone and they repair faster. Every single time I've fed mine silversides repeatedly, I have lost them. I now retain my 3 just perfect, living on phyto and on krill weekly. I only feed one time weekly.
But...what works for me, may not necessarily work for everyone else. I live by Karen's Anemone site's suggestions for mine, and we go right alongside what she recommends, up to the silverside issue. She does recommend feeding silversides, even though experts say not to, and I disagree with her. I have just had too many die on me within a week after feeding them the silversides.
Maybe it's our local silversides...I don't know.
Either way, you could try some krill, chopped into quarter-inch bits.