I recently found this site because my pool was turning green regardless of the amount of chlorine I put into it as the weather was warming up this spring. My LPS was no help, saying I needed new cartridge filters and to keep adding acid because my high TA was the problem. So I began researching on my own and found so many different opinions, but only one that made sense to me. This one!
WIth so so much great information on this site, (and reading through pool school a number of times) I was able to think back to how this problem started. Last spring, my LPS suggested I start by adding the appropriate amount of EZ CLOR, Clor Save (now I know it as CYA) to start the season, it worked fine. Then fall came around and they suggested I use 3" tabs so I don't have the liquid go bad if I don't use it through the winter since it doesn't need much anyway. Sounds fine, I thought. Then this spring, I try to get ahead of the game and add the appropriate amount of Clor Save...because my LPS told me to do it even though they, nor I, had the ability to check the CYA level....bummer.
Two week later I had an algae bloom. I added probably 12 gallons of 12.5% bleach over the next 4 weeks and it just kept getting more green. That's when I found this site. After much reading and figuring out what happened, I decided to drain half the pool water and refill. I then used some calculations I learned from this site to estimate the amount of bleach I would need to get up towards shocking levels. 3 days later, my pool is blue again. I just received my TF-100 last night and took some measurements. It was pretty cool to see how close I was able to get from estimating on the pool calculator to what the result came in at. Anyhow:
FC - 23 last night, 19.5 this morning
CC - 0.5 last night, 0.0 this morning
TC - 23.5
PH - 7.8
CYA - 110ish (slightly above the 100 mark)
TA - 180
CH - 600
The high TA and CH are from the local water. I'll work to get the TA down but not sure if I can do anything about the CH. My CSI is at 0.4 so dropping the TA would decrease that number as well IIUC.
My question is though, how sustainable is it to keep FC at 12 with CYA at 110? Will I constantly be adding bleach? I may run it for a bit just to see, then drain and fill another quarter if it's too much. Thoughts?
Please let me know if you have any suggestions to keep this pool blue!!