We got him yesterday and he was doing well and being active, sifting thru the sand, making burrows all over the tank. Then in the evening he jumped out (fell about 6 feet onto marble flooring) when the lights turned off and thankfully I found him and put him back in. He was probably out of the water 2 mins max. I watched him for about half an hour and he seemed a bit disoriented, but fine. He sifted thru the sand a couple more times around the tank and then I went to bed thinking he was okay. Today, he is nowhere to be found. I checked the floor and behind the tank just to be sure. Is it possible he died under the rocks or is he just hiding? How do I feed him if he won't come out?