Yes, I tested twice and got two different results. Okay, I am SO HAPPY!!!! We put the rest of the CYA in a sock last night, I love that method, I tied it to a rock and put it by the return, I could actually see it dissolving, COOL!! Hope that is correct, that is what I understood to do. I thought I was suppose to have a CC reading, but was just reading somemore and read a 0 reading is good!! Okay, we will work on the sand next. Thanks so much!!