I have 8 chicks currently about 4 days old. They have been on a multi flock chick starter from blue seal, I have started small flats of grass, can I put the whole flat in the brooder and let them go for it? Will this be bad for their crop? Do I have to give chick grit first? Some have pasty butt. I've continued to clean twice a day. First time ever having chickens. Thanks a bunch!