Help with raw shrimp color I bought raw, red Argentina shrimp. In the fridge, I noticed the legs looked like they turned blackish-blue. Does this mean they went bad?
No, blue legs in and of itself is not an indicator of bad shrimp.  Many, if not most (or all), shrimp, lobster, and crayfish are coloured various blues, aquas, and greens before cooking at which point they get their traditional red look.