In reference to your title, has your levels spiked...if so, then he may be dead. If you think that it spiked from moving the top rocks around...it hasn't from that. Have you checked your levels? And about the shrimp, what kind is it, because most shrimps are nocturnal and come out at night; or else he may have molted and may be hiding; or if he is still new, he'll have to get used to his surroundings before coming out. My blood shrimp stayed hidden for 3 weeks before he came out finally.