I have eight two and half week old chicks. One wasn't thriving, was lethargic, not eating and had drooping wings. After researching and talking to my vet, they suggested I try Sulmet. They are on their last day of it and the sick chick is now thriving. However, my Buff Orpington is now all puffed up and lethargic. Wondering if I should have tried Corid? Could I do so now after they've been on Sulmet? I also supplemented their feed with probiotics since they've been on the Sulmet. They go outside for a few hours in the morning in a covered pen and are inside with a heat lamp the rest of the day. We don't use chemicals on our lawn or garden either. Any advice would be greatly appreciated.