Hermit crabs molting

[Danjsim]

I woke up this morning to find the shell of one of my hermits floating around the bottom of the tank, first I thought it died or something had eaten but all of them were alive and moving.

Should I remove the old shell and how often will this happen?

 

I have a 6g tank with 3 hermits, 2 clowns, 1 yellow coral goby. Should I also be looking at getting some more hermits, crabs or snails to clean up.

Thanks.

[Dylan.N]

I always take out the skin. My hermits molt maybe once a month. I would get more snails if you don't have any already.

[Danjsim]

Thanks! Will be getting some snails over the next week