Chris D. I didn't know this information about the white "stuff" at the bottom of the bottle. Thank you. My child is school age and he takes his mid-day dose at school. I've always gotten a small brown bottle from the pharmacy and poured some into that for school. He has been growing too fast lately so I'm glad to know I need to take a full glass bottle to school. Does anyone know what age is good to start with the pill instead of the liquid? My son is seven.