[HERMEZ]

No actually you have been lucky---but when they do molt you may find its too much for them. BUT you should be providing what they need regardless as all may fair well. So since you have been researching please add enough moist sand 2x the largest crab- get them some quality salt water not the junk they sell for hermies. They need the salt to molt and yes they all molt and they molt often when small and as they grow will molt less. I dont know their size but they should be molting every 3 mos at least- if bigger then every 4-6 mos etc etc
They need a fresh diet not commercial pellets etc as it is not really good for them. Read up there is lots of info here.