First I would like to thank everybody for all the great information provided on this site. I have learned so much in the past week reading about FC, CYA, and other chemical levels, but I would appreciate some advice on my particular issues.
I keep my pool covered when not in use. I have the pool filter running at a relative high speed for two hours per day when the booster pump is running the sweeper. Then when the booster pump turns off I reduce the speed of the main pump to circulate water and generate FC through the SWG for another three hours. I have to admit that I don't test my water very often, maybe every two weeks or so.
A couple weeks ago I pulled the cover off and the pool was green with algae. I noticed that at the lower speed, the flow was insufficient and the SWG flow sensor was keeping the SWG cell from turning on. So I backwashed the DE filter, and cleaned the scale off the SWG. I went to the pool store and bought six pounds of BioGuard Shock (Sodium Dichlor). I turned the pump on high, turned on the booster pump/cleaner, and turned the SWG on the boost setting and adjusted the pH. Then I added the six pounds of shock, added two chlorine pucks to the skimmer basket, brushed the pool, and let everything run for about 10 hours. First thing the next morning I turned on the pump, cleaner and SWG and swept the pool again. The pool had cleared considerably and had turned from green to cloudy grey. I tested the water with my cheap tester and the chlorine reading was too dark to read.
That night I found this awesome website and learned so much about all the things I have been doing wrong. Number one was trying to use my SWG in boost mode to clear up an active algae bloom. I always wondered why my FC reading was always coming out zero no matter how long I ran it. The pool store always recommended double shocking and then a maintenance shock once a week.
So here is where I am at now:
First I ordered the TF-100 kit which I should get next week. Then I had a water sample analyzed by the pool store on Tuesday (three days after applying the shock). I know based on what I have read not to trust the results, but they are all I have until next week:
CC: 0 (Deduced because they reported no difference between free chlorine and total chlorine)
Adjusted Total Alk: 82
CH: 535 (reported as Total Hardness not sure if that is only calcium hardness)
Temp (I measured it): 82
The main issue I have been having for the past two years is that the SWG doesn't seem to generate FC like is used to when I first had it installed.
After reading through the information on this site I am starting to think my high CYA level may be causing this. I also now realize that using the chlorine pucks in the winter instead of liquid chlorine, along with shocking weekly, along with very little rainfall the past two years may have caused these elevated CYA levels. Also, my TA level appears to be elevated too.
I know I need to verify these numbers once I get my test kit next week, but it looks like I will need to do a water exchange to lower the CYA and then make sure TA is correct. Do you concur with this assessment? Are there any other recommendations you can suggest?
Thanks in advance,
P.S. Once I get the TF-100 I plan on measuring my pool levels much more frequently!