I am a fairly new pool owner and have been doing some extensive reading here. I understand most of the content but I am a little confused with my chlorine issue. Since the discovery of TFP I have switched over to the BBB method of maintaining my pool. The problem I am having is a 0 FC reading. I had my water tested at a local pool store and I think my problem is the 100 CYA. Chlorine Lock? Should I be checking for other issues that might be eating up the chlorine? My PH is perfect as well as TA. I have a 17 1/2' x 33' inground, 4ft-6ft. Any suggestions on my chlorine issue would be greatly appreciated.