Never had anything missing or buried, besides fish missing. But last year in my Nano, my cleaner shrimp is almost too smart for his own good, like he has no fear, or he's playing with me. Every new frag I would purchase, and they were all small frags, my hand wouldn't even be out of the tank and he would be on top of the coral checkin it out. Then he would push them off the rocks, just so I would have to reach back in and reset them. After 50 times it gets very annoying.