Then this brings up the question - Concernedmommy, do you have an under tank heater on your crab's tank?
If you do, get a kitchen thermometer that will take low temps (if you dont have one you can get one at Walmart for about $3.00 US) and temp the substrate over the UTH.
If it is over about 81*F, this could be the culprit. If your crabs are digging down on top of it, they are probably not registering when it heats up to a high temp, so don't move when they should. You can thin the substrate over the top of it and strategically place items such as heavy dishes, glass beads, etc. to keep them from digging down on top of it.
If this isn't really an option, then for now, unplug it. You can purchase a thermostat to control the temp of your UTH. They are a little pricey, but well worth it. If you are savvy with Ebay you can possibly get one for under $30 including shipping.
If you go this route, make sure it is a thermostat, not a rheostat (with lo-med-high), as you need to have control over the exact temperature. the probe for it should be centered on the glass over the center of the UTH. You can tape it down with clear packing tape on the cord just behind the temperature probe, but don't tape the probe or it won't read correctly. Taping the wire down will keep your little fellers from pulling it up and moving it around (and they will, trust me!).
6 hermit crabs - 3 PPs and 3 Equadorians
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