LOL Lady Godiva! Love that! I agree about the shell size. I set up a hermit crab tank for my godson and he was so excited about finding "the perfect shell"! He put so much work into making it look "super cool"! But unfortunately it was just too big for the little guy. We instead went out and found shells of different sizes. My godson spent lots of time decorating each one and then the crab chose one of the smaller ones. He's since moved onto that first bigger shell that was so carefully crafted for him lol. When we were researching shell sizes, we were also told that sometimes a shell is the right size, but too heavy. There was a problem with a certain brand of store bought glass shells because they were all too heavy for the little crabs. According to the person we spoke to, those particular glass shells are no longer sold though, so if you do go with glass then you shouldn't have a problem.
My godson's second, most recent hermit crab also got the same selection of shells as well as several more options and he actually likes switching between a few shells of the same size. Like how some people have their Monday shirts, their Tuesday shirts, etc. LOL! He doesn't wear certain shells on certain days like that, but some hermit crabs really do seem to enjoy variety!
Another thing to consider is what the inside of the shell feels like. We started shopping for shells at the pet store thinking an employee could help us determine the appropriate size, but a couple of the shells they were trying to sell us felt rough inside and even spiky around the edges that would be in contact with the crab's skin! I wouldn't live in there!
Just doing a quick google search, a couple posts seem to suggest checking the temperature and humidity, but I didn't see recommendations for proper degree or percentage at first glance and I don't remember what the tank stats had to be when I set it up. It's Mom and Dad's responsibility to keep up with that now lol.
Good luck! Hermit crabs seem to be such a favorite among kids! A few of the girls in my youth aikido class told me about theirs (that's how I got the idea for my godson) and love them because it's "art and awesomeness combined"!
