Starting a SLAM, testing for FC and CC using the TP-100 test kit, starting with R-0870 powder. The instructions say to fill the chlorine only vial with 10cc of pool water, then add a scoop of R-0870. If it does not turn pink I have no chlorine. And it does not turn pink. But the regular daily drop test kit shows high chlorine levels. And repeating the R-0870 test with straight 12.5% Chlorine doesn't turn pink either. Could there be something wrong with the R-0870? Can it go bad over time? Or could there be something wrong with the chlorine I've been buying?