We have 2 and 3 week old baby chicks. Started with 30 total, 10 EE's and 20 mixed of white leghorn, gold star, silver lace polish and I think black star. Anyway things went well the first few days and after a week they started dying. I have 17 chicks left healthy at this point. I have been feeding medicated feed from day one and gave vitamins (without iron) for several days. They have a room built just for them in our shop that is about 10x10, with pine on the floor, heater and heat lamp. The room has been devided in two and EE's on one side as they are bigger and smaller ones on the other. They have had food and water at all times. We check on them all through the day and they will all be eating drinking and acting normal. Then when we check there will be one down. The chick was fine one moment and the next it acts as if it just has no energy and can't even stand. They also seem to be having problems breathing at this point. Then they die. I would like to try and figure out why this is happening as we have eggs in the bator and I don't want it to happen to them to. We got the chicks from a local man that orders from several hatcheries then sells the chicks. I did not ask if they had been vacinated so I don't know the answer to that. My husband said he thinks we need to turn off the light for a while daily so then can sleep. I have not heard or read that you need to do this for them but am willing to try just about anything at this point to save the rest. Any help would be greatly appreciated.