At 1 week old I gave my chicks a few crickets that I found outside, but I noticed some diarrhea afterwards; even with the grit. I wondered whether it was the crickets or the grit that caused the diarrhea. At 2 weeks old they are tolerating both small amounts of cheerios and crickets without any signs of diarrhea. The cheerios are a fun treat to feed, because unlike the crickets they can't quite figure out how to eat them. They usually just play keep away with them and (maybe) each chick gets a crumb or two.