I moved into our home two weeks ago. The old owner left som "Aqua Chem DE Media + Filter Aid". I backed washed my pool this past friday and used this DE to re-charge the system. I got curious about the "+ Filter Aid" claim on the box. I searched the web and every add says it is 100% DE. The question is what is "+ Filter Aid"? Is it a marketing thing? "My DE is better than your DE"