The higher priced DE is the food grade. My feed store gets almost $14 for a 1.5 lb bag. There are different grades from what I understand. Be sure you are getting the grade you want.I went to a feed store today to get DE and they wanted 59.99 for a 40lb bag!!! Ridiculous!!! I am going to the feed store by my job or tractor supply tomorrow. They have it for 15.99 or 19.99 for a 40-50lb bag.