I recently bought 6 hens that are already laying. They are about 1 1/2 yrs. They came from an older couple who kept them in good living conditions with a lot of space. They looked all around healthy and I checked them for mites/lice and found none. When i brought them home I kept them seperate from the chickens I already have just to be cautious. I noticed that one of the hens does a hissing kind of noise and another one sounds like she is sneezing. So I put them on Aeromycin for 7 days given in the water. It has not helped. I also noticed diarhea in the pen. It looks like just straight clear liquid. I watched them closely and spotted the hen with the problem and now there is another hen with diarhea but hers is a light brown and not pure water it is more gooey. They are aracauna hens and are laying well and eating and drinking well. They don't seem to feel bad. Also when I stopped the antibiotic I gave them yogurt to help with the digestive system. Now I have noticed that some of my 7 week old chicks have the light brown almost reddish looking diarhea too. I just wormed them about 5 days ago with Wazine. They all look healthy and are eating and drinking fine and playing also. They get yogurt as well. I give all the chickens the same treats at the same time so they don't feel left out. Their pens are open on all sides so there is plent of air circulation and they have fresh food and water every day. Their pens are very clean and the hens laying boxes get cleaned out about every 3-4 days. I am freaking out about the thought of cocci. Anyone have any suggestions or input?