"I've found a few bits of glass in this stuff that is just NOT safe. It's fine after you pick it out, but sometimes it takes a while to notice it. HUGE safety hazard for any critter kept with this substrate. I used to use it for my tarantula, but switched to aquarium gravel and soil from the woods after I found the glass. Holds moisture great, but you might want to check it for glass before returning your critter to his/her home."