I'm going on year 5 of pool ownership and I've had algae before. Usually it clears up with some heavy shocking and brushing, but this time nothing is doing it, so I am finally registering after reading some TFP searches in the past. The big problem I think I have is that my CYA is more than 100, so the SLAM process wants me to get my FC Up to 39ppm, and I'm not successful in keeping it that high. I even tried the 3% copper which worked in the past for me, and it's still green.
I don't have the accurate test kit yet, nobody local sells it, but every day I was able to read my levels on my normal DPD (so under 5ppm) and I'd add more per the calculator. Last night I put in 4 gallons of 8.25% Clorox and this morning the FC was reading 3ppm and pH is up to 8.0 (it was 7.5 when I started Friday night). I only had 2 gallons to add before work. So question one is: Did I just go backwards since I won't be home until 6pm to add more?
Question 2 is: should keep on pumping money into chemicals, or if I should invest in draining half my pool to get the CYA down? It's a 12k gallon Pebbletek pool in Phoenix, AZ, with the weekly high/low temps looking like this:
111/74; 109/72; 110/71; 110/71
I feel like #2 is the better option since it fixes a root cause, but it might be risky? I'd be starting around sundown (as to not be up all night) so the temps would still be in the 90s I suspect.
Thanks for all the help from my past searches and for this too!