Getting CYA to required level

[jonesy119]

Hello,

Over the past month or so I've added about 5 lbs (approx 2.5 lb twice a month apart using sock in skimmer method) of Pool Time's Chlorine Stabilizer as I'm not sure there was any CYA in the pool when I bought the home, or at least Taylor's test kit said so.

But Taylor is still reading it at 30 - 40, when I should be around 80 at least given the size of my pool.

My questions are:

- How reliable is Taylor's kit with CYA? I know it's supposed to be read when the black dot "disappears", but doing research some owners don't seem to trust it

- I've found I need to add about an inch or so of water every couple days due to evaporation. I wouldn't think that would have such a dramatic effect on reducing CYA though.

- Or maybe Pool Time's Chlorine Stabilizer is just a poor product?

- Some other reason my pool can't seem to maintain CYA and\or won't rise to acceptable levels?

Thanks!


FC 5
CC .2 - .5
PH 7.4
TA 90

 

[jonesy119]

I forgot to mention ...

Prior to adding my last 2.5 lb or so of Chlorine Stabilizer, my SWG was averaging about 3500. For the last few days, after all the stabilizer had dissolved, it's been about 2900. Could that be an indication my CYA is at a "workable" level? Seems to stand to reason if the CYA is protecting the chlorine from UVA and I'm losing less, the SWG doesn't have to generate as much.

Also, my FC has been stable around 5 for the past week or so (pretty much daily testing). If I didn't have enough CYA I would think I'd see some fluctuation.

 

[duraleigh]

5 lbs of CYA in your 16k pool raises CYA to around 40 ppm. Use PoolMath to calc your dosages.

Taylor's CYA test is as good as it gets. The electronic ones and the strips are not good at all.

 

[jonesy119]

Thanks, Dave.

"5 lbs of CYA in your 16k pool raises CYA to around 40 ppm"

Well, that would certainly match the readings I'm getting. I've seem some inconsistencies regarding how much CYA to add, including the Pool Time product itself. Looks like I went light.

I'll keep adding about 2 lb a pop until I get it to where I want it.

 

[Richard320]

Going light on the CYA is better than going heavy Adding is easy. Removing is hard.

And Dave's not a wizard. He cheated by scrolling down near the bottom of poolmath where it shows effects of adding chemicals. You can use that feature, too. It will even show you roughly how much pH will shift with the CYA addition.

 

[laprjns]

- I've found I need to add about an inch or so of water every couple days due to evaporation. I wouldn't think that would have such a dramatic effect on reducing CYA though.

Losing water through evaporation does not reduce cya.