Okay. So the reason amano and ghost shrimp turn pink when they die is because they have pink or red pigments called carotenoids in their body. While alive, these pigments are covered by a chain of proteins that hide the color. When the shrimp dies, those proteins break down, exposing the red pigments and giving the dead shrimp a pink color. The same thing is why lobsters turn red when you cook them, because the heat breaks down the protein cover and exposes the carotenoids. And flamingos are pink because they eat a lot of shrimp and when the proteins break down after the birds consume the shrimp, the carotenoids are processed into the feathers of the flamingo. If you change a flamingo's diet the bird will gradually lose its pink color and become white.
As for the cuttlebone. I have always kept a chunk of cuttlebone in any tank in which I have ornamental snails or shrimp, to ensure there was enough calcium in the tank. I've seen snails and shrimp "grazing" on it. I also have hard water anyways, though. I've kept cherry shrimp and ghost shrimp, and I've never had a problem with losing shrimp unexpectedly and I've always had both breed regularly. I keep the cuttlebone in the tanks because it's recommended and I do it as a "best" practice type of thing. I don't know if adding cuttlebone will be enough or not for you though, Ice, to be honest. I just don't have enough experience with shrimp and since mine have always done well I never really explored the causes of problems much.
You also have to remember that most shrimp are fairly short-lived. I think amanos can live 4 or 5 years, though. Even if they weren't juveniles I'd expect them to live longer than two weeks, unless there was an underlying problem. Cuttlebone can't hurt IMO, but I won't guarantee it's the remedy you need.
WYite
