The time it takes for a crab to complete a molt varies. As a general rule, the larger the crab, the longer the whole process will take. It is not unusual for an average-sized crab to spend about four to eight weeks going through the whole process, during which time it may stay completely buried in the sand.

How do you know when a hermit crab is molting?

A molting crab appears quite limp and lifeless, and the body is often partway out of the shell. 1 Sometimes, with very careful observation, you will be able to see small twitches from the hermit crab's body while it is molting, but otherwise, it can be very difficult to tell whether or not it is still alive.

Do hermit crabs eat while molting?

Crabs that are molting are not concerned with food and digestion. ... Once they complete shedding, they eat their exoskeleton and, because all nutrients from the exoskeleton are absorbed, the a crab eating its exoskeleton does not produce the amount of feces that an un-molting crab produces.