I buy scallops, shrimp, fresh fish.
I cut it all up and put it in a ziplock bag, spread out, and put in freezer. Then I bang the bag once and it all falls to the bottom and take out a peice or two at random.
I usually make it dime to nickle size pieces, lately, but I used to ONLY do pee size.
Drop it in a cup of tank water, let it thaw while I check out and do the daily maint (5 minutes) and then feed away.
But deff always use FRESH.