Honestly, I don’t get it either unless I am testing wrong. When I put the chlorine bleach in the pool the FC is 0. I take my first sample about 30 minutes after I add three gallons of chlorine. I use two dippers of the powder. It turns it red! Then it take 160 to 180 drops to get the water in the test kit to get clear. I’ve tested for cc on May 13 it was 5.2. May 14 the cc was .8. Now I’m out of the R 0871 liquid for testing! And my water looks beautiful! Shew! This is an rural. I’m not giving up though. I have to say the granddaughters are getting a bit antsy. They want to swim��. I’ll update when I find the regrant hopefully around here in the morning so I can test.