Dehydrating question

When i dehydrated my flush, i put it on 120 deg for 10 hours, and they came out like crackers, which i was told was good. Put in a jar with a couple of silica packs, but after a few days, they were bendy again. My question is this...when i want to make powder, should i do it right when i take it out of the dehydrator? Als, can you re-dehydrate to get that cracker consistency back? TIA