Hermit crabs do molt to allow themselves to grow. During the molting process, hermit crabs shed their current exoskeleton. At that time, hermit crabs may grow a new shell or switch to a larger shell if provided.
Molting is a normal, healthy process for hermit crabs. However, the process of molting - shedding an existing exoskeleton and growing or moving into a new one - might seem unusual to those unfamiliar with it.
If a hermit crab has outgrown or become too small for its current shell (also called its exoskeleton), it may begin the molting process.
First things first: no matter what – don’t disturb a hermit crab throughout any part of the molting process!
Hermit crabs that are almost ready to begin the molting process can be seen eating more and spending more time in their freshwater and saltwater dishes. A reserve of food, water, and salt allows hermit crabs to break their old exoskeleton and survive the process.