couple questions for ya. do you dose anything? and what fish are you keeping? do you use tap or Ro water? How old is that tank you put them in?
bamboos are very shy, and tempermental. i lost 3 before i was able to keep them, currently i'm keeping 3 and 1 vampire shrimp.
that fire red one molted in store, and his color should begin to fade in the coming weeks. the other one seems to be having trouble with his molt, as was said above. do you have a cave or some hiding spot for the one that is trying molt? sorry more questions than answers right now. just trying to get an idea of what is going on in the tank to help figure out what is going wrong here.
OH! and what did you spot feed them?
in the mean time, if you have zucchini or squash boil it until soft and place in the tank near them.