First, I should confirm what diatomaceous earth is. Diatomaceous earth is made from fossilized remains of diatoms, which are hard-shelled algae. It's known for its high porosity, low density, and abrasive properties. It's used in various industries like filtration, food processing, pest control, and as a flow aid in powders. But what's special about the ED30 grade? Maybe the particle size distribution or the specific surface area.