My girls were on a unmedicated chick starter from a farm supply shop. they were close to finishing and i bought a new kind of starter/grower from another store that buys from our local feed coop. i mixed the first few trough fulls about 50/50 but they ate it so fast and i ran out of the original feeder. we have noticed runny poop. is this because the switch over to fast or the recent intro of worms to their diet?