I'd like to suggest a fingernail size piece of fresh seafood such as perch, flounder, bluefish, shrimp, etc., instead of silversides. You're on the right track just continue to chase the clownfish away for a good 10-15 minutes after the anemone eats. Eventually the anemone will develop a faster feeding response and the clownfish will be less of a nuisance.
Just went through the same ordeal with my current sebae of 11 months (was the size of a scallop), makes me regret selling the last one. I still need to distract my clownfish but nothing like the first 6 or so months. Tried the basket (shield) trick only to find it's edge on top of the anemone because of the clown's excavating. It was shriveled up, turned it's stomach inside out, detached, looked like a goner. Took a month to regain it's prior good condition.
It occasionally eats food that the clownfish drops (too large or the clown has trouble, like non-peeled shrimp legs and tails), to pick at latter. I'd think your anemone is eating something, it's coloring up well, try the above suggestions. I don't like saying this but keep in mind that ill health may not be obvious till it's too late. when they starve they feed on their own tissues which is thought to be irreversible.
Good luck, it should be alright, keep us posted.