the tank is located in an atrium that is about 15 by 12 feet and at least a foot lowered into the ground. i dont think he could have climbed the stairs to get out. so obviously he has to be in it somewhere. the atrium is filled with plants, and rocks and small trees. some of it is dirt and mulch and other part is small stones to step on. we have searched what seems like the entire room. we moved rocks and have moved around the mulch. i know they like to dig but how deep would or could he go? do they prefer different environments to dig in then others? can he move stones the size of himself and bury under them? could he be hibernating? (i thought they only did that in water). any ideas on how to find him would be great. thought about putting my dog in there and maybe he would find him by scent though there is lava rock in there and he could get hurt or try to eat the turtle if he did find him. i dont know what else to do or if it is too late. i was away when my mom lost him (it was about 2-3 weeks ago. i'm hoping he's hibernating...

