I started using the BBB method last year and had no problems. This year is a different story. I've been fighting my pool since I opened it three weeks ago to maintain a FC reading. I am trying the shocking method right now described on this website, but don't know if it will ever work! I thought I had it yesterday, but I dropped to 0 FC while I was at work today, so I started again.
My water is clear. My CC is .5, but I am dropping about 5 ppm overnight. How long will this go on? I am adding chlorine tonight every 2 hours tonight to maintain 20 ppm. It dropped about 4 ppm in 2 hours this evening (with little sun). I am really afraid that I'll bleach my new liner. Any advice??
Here's my numbers using the TF-100 kit:
FC - 20 ppm
TA - 120
PH - 7.5
CC - 0.5
CYA - 50
20,000 gallon inground pool/vinyl liner