I've always just gotten a plastic cup or any other small dish (make sure it is clean, no soap residue!), dipped it in the tank and filled it full of water, then put the frozen food in there, let it thaw for a while, and when all thawed out, just dump the solution back into the tank. I often add garlic to the mix when it is thawing. I don't believe you would have to hand feed them, I've had both of the shrimp you mentioned, and they've never had a problem catching their own meals. You may want to add a few hermit crabs and snails to bulk up your clean up crew. If you have a decent clean up crew, anything that isn't consumed by your shrimp (or eventually shrimp) will be devoured by the crew.
Good luck!
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