Just wanted to post my thanks to all contributors who helped a Newbie Lurker get control of his pool. Had major algae bloom and threw a bunch of chemicals into it with no real scientific approach. With no success, I admitted defeat and came here for advice. Learned my basic pool science, followed the shock thread (Thanks JasonLions) and developed some patience.
Of course, similar with other stories, the key to my success was getting a good test kit. I think it has already paid for itself (TF-100)
Determined my shock levels with the charts (I was not even getting my FC CLOSE to real shock levels prior to that). Kept my FC at about 23-25 for 4 days, often required shocking twice a day. I saw almost NO results for the first 48 hours, but just kept my chemistry right and kept brushing the pool. I got a little impatient and went and bought some DE to speed things up. I started seeing better results right away.
Now I am at day 6, my pool is sparkling clear, and my FC is around 21. I did a chlorine drop test last night after dark (FC 23) and fell to 21 early this morning. Should I hold on adding more shock at this point and just keep checking my chlorine drop overnight? If it drops less than one overnight, I can stop the shock process, right?
Pics at day 1[attachment=1:34yoqwag]IMG_2472.jpeg[/attachment:34yoqwag] and day 6 [attachment=0:34yoqwag]photo.jpeg[/attachment:34yoqwag]. I have some slight metal staining on the front ledge that I will eventually use ascorbic acid on... but that's for another day.
thanks to all for your help.