I'm new to TFP as of last July. This place is miraculous. My story.
I've had my pool (27' diameter) for 7 or 8 years. Two years ago started having a problem getting a chlorine reading. Was able to get the water looking OK but struggled with it going green (no chlorine, hmmm, I wonder why). Went to the local pool store and got a small box of chemicals and spent over $100. Didn't fix my problem. "Bring your water in again and we'll tell you what you need." "You may have chlorine lock." "You'll need massive amounts of shock." I struggled through the season and was glad when I could close the pool.
Last year started the same way. Couldn't get a chlorine reading. Started getting serious on the web searching for an answer. Many articles about chlorine lock. I was believing it. Went to the local pool store. Same situation- buy lots of their chemicals and hope for the best. After testing my water, they "confirmed" that I had chlorine lock. "You'll need 48 bags of shock." Yikes!! This didn't sound right.
Back to the internet and finally stumbled on to this site. After lurking around trying to see if this was legit or another bogus site, I became a believer or was at least desperate enough to try the TFPC method and SLAMing my pool. I was on vacation in mid July of last year and after having purchased a TF100 test kit started slamming. Long story short, three days and 28 gallons of shock later problem solved !!! Slamming really worked. My pool was easy to take care of the rest of the season.
Started out this year with a green pond (need a new winter cover). Started slamming on a Saturday and by next Saturday we were swimming. It took a few weeks for it to really sparkle but it is beautiful now and easy to maintain.
I bought my chemicals from Rural King (liquid chlorine to shock, 3" tabs and 4# of CYA) and only spent just over $100 for my seasons worth of chemicals. No clarifier, no Phosfree, no mineral cartridges, no algaecide, etc, etc. (all things that I bought before).
TFP.com is the best and I share this story all the time with others that have pools.