I found a 50lb bag of DE for $50 online from diatomaceousearth.com but it is listed as food grade. Is that a good price and is food grade ok for the pool filter?
Next, I can order a 50lb bag of calcium chloride marketed as Snow Joe Ice Melt from Home Depot for $15, but it looks like the crystals are quite large. Maybe the image on the Home Depot website is throwing me off, but they look like the size of chocolate chips. Normal?
Finally, Home Depot sells 2 gals muriatic acid 31.45% for $11. Is that a good deal?