Bought the TF100 chlorine test only (since I have taylor K-2005C) and I am doing a bucket test right now to see how much chlorine my water is going to consume. We suspect an ammonia or fertilizer problem in general. I added 3 tsp 6% bleach to bring it to around 50FC. In an hour I tested it to be around 3 FC but when I left it sit a second it turned pink again. In fact if I let it sit for a few minutes it turns brilliant pink and tests another 3. Is this my high cya (just over 100) affecting test results? I'm a bit confused.