Turning White

Question
Hello,
I am a new hermit crab owner.  The bigger one, Fred, I got first.  He is very active and very friendly.  About a week later I got another, Maple, she is smaller.  They seemed to have got along well when I was introducing them.  When I woke up the other morning Maple had lost a leg.  I was nervous.  Then I noticed that she started turning white on her legs.  Also she is keeping one leg out when she goes into her shell.  Now I am noticing that Fred is slowly turning white.  Do you know what this is?  I would appreciate any advise you can give me.
Thanks,
Kerri

Answer
Hmmmm, I need a little more information if you don't mind. What kind of tank are they in and what is the substrate? What do you feed them and what kinds of water do they get? What is the humidity and temperature in your tank.

With this info I'll be able to tell you what's going on.