Just keep thinking about seeing Tiger, and I'm sure the flight won't be too bad! 
Oyster shells would work, as would anything you have on hand. I wasn't suggesting running out for anything! I know you beachcomb and have loads of stuff already, on top of the stuff you have for the adult crabs.
If you go the false bottom route (which is what the epoxy sand beds are called), make sure to make something outside of the tank that you can drop into place. Many a big expensive tank has been lost when a reef keeper tried to pour the epoxy into the tank to make it permanent. The heat from the curing epoxy, along with the fact that it expands and contracts as it cures will crack and/or shatter the glass.
I got to meet one of the mods from the Roach Forum in person yesterday and was telling him about your endeavors, and he suggested maybe at this point they would have to be separated from each other for safety. I forgot that in with arachnids (and some insects) cannibalism of siblings is a normal thing that occurs over time. If I get that far I will probably try keeping some communally and some separately because of this. It might just be normal, or it might be in response to lack of proper food. (But what that food would be, I don't know.
)I still think it's absolutely amazing that you got this far!!! Everything you have shared is advancing what we know about breeding them.
There are no guides for this, and so much of it is experimental that them not making it is in no way a failure. You got them farther than anyone in the home hobby so far, and you got them as far as the scientific journals have reported. (ONE got that far in the papers - you have hundreds!!) That's a win. That is totally a win! And that's also how breeding programs get started - you try things, and then the next time you build upon what worked and what didn't and you get farther, and the times after that you keep refining it until you make it work. You just gave everyone here a very solid base to start on, and it will hopefully only take a few more tries to get it working. You documented everything, and those photos are incredible! For all you know you're inspiring more research into this by some grad student somewhere and we may be learning even more about them and captive breeding in the future. You are my hero right now for putting yourself out and trying this, I really hope you know that!! Everyone I know has been told of "Wolf and her babies" whether they have hermit crabs or not, and everyone I know is pulling for those little guys and thinks that you're one awesome lady for being so ground-breaking. (For them you're already awesome for living in Alaska, so trying this makes you even more awesome.
Must be an Ohio thing. 
) You inspired me to put my absolute all into trying it as well, and I hope to heck that I can make you proud by getting just as far. 
I'm definitely glad that I was able to document everything. I hope one of us someday is able to breed them 100% all the way through. It would also be neat to have like...1st, 2nd, 3rd generation captivity crabs in the future. 
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