Mysis and Rod's. The brine doesn't provide much, if any, nutrition.
Mu cbb likes a seafood blend I make. Buy a couple of scallops, a couple of shrimp, and a small piece of fish (I am currently using salmon), all fresh from your grocery store. Chop it up and freeze it is a couple of small ziplock bags. Each day, take a paring knife and slice off a spoonful of small pieces, and drop them in the tank. Not quite as easy as buying a frozen fish food, but it is not much work and provides the fish with quality food.
Start with just one or two scallops and shrimp, and a piece of fish about the same size. $10 of this mix lasts a long time (at least 4 months feeding every morning).