What is de for the filter and where do I get it? I have ordered ben's test kit meanwhile all I have is aquachem from walmart. it says that I can't test for ph ta or hardness until I get my chlorine down to 5. soooo I only have test numbers from before I shocked the pool. I will try the de if I can find it anywhere around here.... smallish town but there are a few pool stores. I am also planning to keep the chlorine at 25ppm for at least 3 more days????? does this sound right.