Normal
I suggest an inch of substrate. I don't find dead nymphs at all..only the occasional dead senior, usually female. They are found in rotted vegetation and leaf litter in the wild. Forest floor. I would also suggest that a tank completely dry with water crystals would be unnatural to them, and not conductive to a normal, healthy life, but breeders raise massive amounts that way, so I would be wrong. Just thinking out loud, I suppose. But I guess the substrate allows for them to flip themselves back over?