HCA: Hermit Crab Association

My crab has been like this for few hours.

It is my first time seeing his eyes pointing downwards.

Is he molting, sleeping or dead?

He ate last night (probably 6-8hrs ago) and kept digging hole for a week. Is it possible he is just molting?

https://imgur.com/RQ7RPvw

Not molting. Is your substrate deep enough (at least 6 inches or thee times as deep as your largest crab) and the right consistency (moist enough to hold shape but not so wet that it puddles) so he can dig down? Crabs should dig and bury themselves completely, in a molting cave to molt. You should not see them. If they are molting on the surface, something is wrong.
Probably not dead if only like that for an hour.
What's he doing now?

Sometimes my crabs will sit like that in one spot for hours. I have read about that on here. When they sit motionless half in, half out of their shell like that they are usually resting.

http://www.hermitcrabassociation.com/ph ... 3#p1070585

Thanks so much!

The substrate should be deep enough and I spray the substrate every day, so it should be moist enough too. He keeps digging in the corners.

Just want to ask one more question: my hermit crab is about the size of tennis-ball, I have read some readings saying that this large size hermit crab will dig hole to prepare for molting, but finally they will molt on the surface, is that true? Or they still molt inside the molting cave?

He is now awake and looking around. So, he should be resting just now.

Thanks so much guys

No, he should not molt on the surface. He should dig underneath the substrate and you should not see him when he is molting.
If he is that big, your substrate will need to be quite deep. How many inches is it? What do you use for substrate? What are the temperature and humidity levels in your tank?

The substrate should be a minimum of 3 times more than the size of your largest crab. If a tennis ball is about 3" you will need a minimum of 9-10 inches for him to completely bury and cover. If it isn't deep enough after he sheds his exo skeleton other crabs may smell him and cannibalize him. Crabs are like zombies, they like the taste and smell of molting crabs.