Thanks for the feedback. I am not feeding them medicated starter, I just looked at the bag of feed. So, I should get the corid and give it to all of them?
This is a judgment call on your part...how BAD do they look?
I've stopped a mild coccidiosis with medicated feed, which does NOT cure coccidiosis. It is Amprolium based medication which is a thiamin inhibitor that slows down the growth of the protozoa (coccida) enough to allow the bird's natural immune system to build resistance to the coccida growth in its intestines to keep it in check.
If however you've got some symptoms of coccidia overgrowth (coccidiosis), then, as they are exponentially multiplying, you've got to more quickly break that cycle or you risk real trouble. Chicks can go from health to death in a matter of a day or two when the coccidia level reaches critical mass as they coccidia are literally eating into the intestinal walls producing the massive blood loss in diarrhea which can lead to permanent scarring and lifelong unthriftiness.
If you've got a mild problem, medicated feed for a number of weeks (4 to 6) can get yourself ahead. If however, you've gotten behind the overgrowth, the best thing to do is hit it with the Corid (which is Amprolium at a higher dose to eradicate the coccidia) then follow up with medicated feed for a number of weeks to wean them off so that their natural immune systems take over....offering further gut support with probiotics and ACV.
Some loose diarrhea in chicks here and there, especially in an overly warm day or brooder, isn't a big thing, just put probiotics and ACVin the water and keep it there.
However a week long of diarrhea that smells bad is a sign of trouble.
LofMc