HCA: Hermit Crab Association

I have roaches in my crabitat. From tiny babies that hang out in the food dish, to adults that hide out in the driftwood decoration. What is the best way to get rid of them? I currently have two crabs that have burrowed under the sand, been there for several days. I might add here that they do this regularly, burrow underground for several days to a few weeks, come up and hang awhile and resubmerge. They tend to take turns. Ha. Please help. I have read elsewhere on this site that my humidity might be too high. My gauge said it was around 92. I have turned off the bubbling air in their water dish, and opened the lid to let some of the humidity out. I don't know what else to do other than remove the three that are above ground, take the whole tank outside and dump everything out and rinse it. However, I can't because of the two underground. I'm at a loss. :/

I'd recommend removing the ones that are up and all decor, and scraping off the top of the sub and killing any roaches you see. Roaches reproduce either using live birth or through fairly large egg cases. You should be able to see anything left behind if they are laying in the tank.

You can keep more from getting in by making a ring of vasoline around the outside of the glass tank. Roaches cannot crawl over this. It should help stop the problem until you can figure out where they are coming from!