I haven't been able to find grit for 10 day olds at the store. TSC's chicken grit states it's for 8 week and older. I also checked the parakeet grit at the pet store, but it says it's high in calcium and I read here that the chicks shouldn't get a lot of calcium until they're at laying age. So, here's my question. My driveway is stabilized gravel - would it be ok to get a small bowl's worth of the tiny rocks in that and give to the chicks?