I just tested my water for chlorine levels using the drop test. I tested for FC by adding one heaping scoop of R-0870 powder. The water turned pink as expected. Next I added 5 drops of R-0871 and the water turn clear again.. When I try testing for CC by adding 5 drops of R-0003, the water remains clear, which per the directions of the TF-100 kit it means I have no chlorine. How is this possible? I am confused. Please advice.