Go to youtube and put in "Bob Fenner anemone 2017" . About half way thru he talks about feeding(around 24 minute mark). I do what he says. So I'm feeding a new to me anemone right after putting it in my tank and every day for the first month. Then move to every other day(at least 4 feedings a week) for as long as I own it. A bleached anemone gets feed every day for months until it gets it "color" back.
I love how he says "fishes". I thought it was: look at that fish, look at those fish(not fishes).
My Nems thrive, and I feed them dried krill one time every few months. They are filter feeders and pick up most of what they need from the water column and off of hosting Clowns.