HCA: Hermit Crab Association

I don't think my crabs will molt soon...But when they do I have some questions.1. Do they lose their shell upon digging, burial or coming up? Do they have their shell the whole molt?2. What does the exo look like, I imagine it looks like a hermit crabs snake skin.If shedding the skin takes one day, how come they stay down there for so long?Any help would rock!

A premolt period can be lengthy and typical behavior can include any of the following: cloudy eyes, confused or tangled looking antenna, ashy exo, downward cast eyes, lethargy, increase in eating, drinking or digging, decrease in eating, drinking or digging, presence of a molt sac, soaking in the salt water, shell shopping, unusually cranky from a normally docile crab.Some go right down and get straight to business, others do something of a trial run going down and popping back up again for a few days or more before they stay down.Once the molt begins they stay down till it's over. They build up pressure to crack and split the exo and then slip it off from their heads and pull their limbs free. If the substrate is dry and lacking proper humidity the crab may struggle and get stuck, shedding the exo in pieces rather than all at once. A shed exo will have eyestalks but no eyes or abdomen and once pushed from the face of the shell it slumps and can be mistaken for a passed crab. Limbs and torso will be hollow. Here's a pic of an intact exo. Small crabs molt frequently and large crabs molt every 12-18 months. As their exos are much thicker and larger their job is much harder and more demanding and they take longer to molt and recover.They rest for 2 days on average and their exo hardens enough for them to begin breaking and eating the old exo for the calcium and nutrients it contains. As they draw the chitin (I believe it is) from the old one to help build the new, the old is very brittle and easily broken.Post molt hermits have a habit of appearing for a drink, bite or maybe even a little tooling around on the surface and then disappear again for a little more rest before returning for good. You should offer a calcium source 24/7 in the tank but post molt they enjoy it even more.Crabs molt in their shells *usually*, there's always the exception and E's are more prone to naked molting I believe. Shell shopping can occur pre or post, really depends on the premolt fit and how heavy the shell is. On rare occasion a crab will actually downsize looking for something lighter and easier to carry.