I took over this pool about two years ago, and with your help I've been mostly successful *(Finally!)- do you think I'm missing something?
For the first 10-12 years only pucks were used. NEVER had a full/partial drain. Minimal water quality problems, at least that I know of. Only ever tested 'basic' chlorine/pH with cheap drop tests. Used same test kit for many years at a time.
Starting two years ago:
Year one, basically same as before- started having mustard algae issues periodically. A lot of difficulty maintaining pH levels.
Year two- found TFP. Started testing more often with a better quality kit. Switched to liquid chlorine. pH became fairly stable. Mustard algae never returned once I dedicated to TFP methods!
CYA- was never 'high'; testing range over past year has been 30-40. (I expected it to be very high- right?)
FC/TC- in the beginning there was an occasional variance (meaning CC was NOT 0), but it self corrected rather quickly. Within 3 months, FC/TC was consistently equal.
**I did miss the importance of the better TC/FC/CC test kit.
I just returned from being out of town for five weeks, found a green-ish pool when I got home. Weather had warmed above 70 for a couple days. I raised pH to 7.5, pouring acid above steps where growth was most abundant. Almost immediately the green growth was eradicated there, green hue to water gone- just cloudy at this point. Next day, I added 2 gal. bleach (per pool math using fresh test), this time pouring at 'other step' where there was growth. Now there is NO green, NO growth spots, just cloudy- I'd say the water appears 'thick' more than it is 'cloudy' if that makes any sense.
1. Continue SLAM? I'm concerned about getting FC down again in this cooler weather. Dogs drink from pool, can't prevent it no matter how hard we try.
2. Do you think I'm doing something wrong in the testing? Sure seems like CYA should be much higher- 12 years of (mostly) puck use (and shock 'bags') plus evaporation- never drained any of the water. (ie, where did all that stabilizer go?)
3. A lot of scale buildup at water line- suggested procedure? Can I drain just below the scale line, acid&scrub scale (scrubbing alone won't do), then drain the recommended 30% (due to 400-420 CH) after a few days of filtering to remove the particulates released?
**Would it be better to acid and scrub 2-4 tiles at time over the course of several months? (1-3x per week)
CH 420 (at 38 drops went purple, 39-41 blue-purple)
Yesterday CYA- 35
Water Temp 58
Anticipating mid-high 70s over the next week.