I never feed brine I always fed frozen cut shrimp. Raw shrimp ya buy for cold shrimp or what not. Just un thaw it and cut into pieces. Or make your own mix food.
Get a blender and take everything. Take shrimp, squid, scallops, clam, seaweed, some garilic and juice and even some flake food and then some nutrients (liguid form) and blend all up. Place in ice cube trays to freeze. Then place in freezer bags and cut off a piece to feed as needed. Works great.