Hello, i have used pine shavings,(first week paper towels)never had a problem. I use shavings for 2 weeks,then switch to sand. Chicks probably were ill when you purchased them. I believe cocci has a 4-7 day incubation period. Do not give chicks any vitamins while treating them,and no protein foods,will interfere with medication. Give vitamins after treatment. I also re-treat in 2 weeks for 2-3 days,just to make sure bacteria is under control. Cocci thrives in damp conditions,keep shavings dry,and water/feed bowls clean. Chicks will recover,takes a couple of days. Respiratory issues can also accompany cocci,this would be a separate medication. Also after re-reading your post,i am concerned that you are not treating ALL chicks,they all have to be treated IF it is cocci. Do not use newspaper,just paper towels. Hope all chicks will be ok.