Update: I am so upset. I dropped the poo by Yvette vet's office and called them back five hours later because I hadn't heard anything. The tech said the doc told her to let me know ny chicks were "full tho the brim with coccidia" and to continue Corid. I explained that I was still seeing blood, but a little less, and that they had been on Corid for three days now and that was why I was seeking the help of the vet. I asked if they might have a Corid-resistant strain and told her to ask him if I needed something stronger, perhaps a sulfa drug. She went away for a few minutes and came back to tell me that, no, I didn't need to give them something else and that the Corid would work eventually and they would need the full 10 days. There were no other parasites present. I spoke to the bird specialist today to confirm that was the correct course of treatment, and he said, "Yes, you have to stick with the Corid." I just want it to work faster and my babies to get better!