I had recieved 30 chicks last friday, 20 Rhode Island Reds, 4 Americaunas and 6 White Plymouth Rock. Through the course of four days I lost 11 chicks and all 11 did exactly what yours is doing. We did the samething as well. They didn't all die at once but after you nursed each one it looked like it was going to survive and then on the side they went later and died. I tributed all of their deaths to the mishandling from the post office. The post office never called, the stupid postman had them in his truck all morning long until they could be delivered in the afternoon. So, I am picking up more chicks tomorrow locally to replenish the ones I've lost.