Feeling a little frustrated. I purchased two new pullets a week ago & it's been a mess. I've never had sick chickens before. Background : they came with lice so I dusted them with DE & sprayed them with poultry protector. Then one had runny foamy poop so they are in day three of Corid & it's firmed up & looking normal but now one is sneezing & has clear water like discharge coming from her nostril and was breathing with her beak open a little bit while resting.I don't hear any weezing and they are eating & drinking. I have duramycin 72-200 here but not sure I should or how to administer it. Any advice would be much appreciated.