I give them all the same feed. Dumor starter grower. I heard if you give the CX less protein and feed meals instead of all day food access then they don't have the health issues. I have three week old CX from Meyer and I am doing that and they are active like normal chicks. They don't lay around all day. Also I looked through a chicken catalogue and it looks like I bought bearded porcelain d'uccle bantam and not Cochin. Still cute though. Have to check as more feathers grow.