Dead or Alive?

Question
Hi,
  Yesterday i checked on my crab which is molting. I discovered that its whole
body turned pink and it wasn't moving at all. I smelled some fishy scent. I am
not sure if its dead.  

Answer
Unfortunately, that fishy smell almost always means death. I would continue to watch the crab a little longer and if the fishy smell gets stronger I'm afraid your crab has passed. You can also try moving the crab to a new location to try to determine if the smell is from your crab or from something in the tank.