CYA and tabs help

Apr 4, 2017
18
Prosper/ TX
Just took over from our free 2 months of service. The guy had used 2 tabs in the chlorinator religiously and my numbers have always been pretty good. While I'm waiting for my test kit to arrive I threw 2 more in last Friday, of the Clorox brand "blue" ones. I took a sample to Leslie's yesterday and CYA was 60, today read 70. According to the chart this is a little high, but since their numbers were off so bad, could it even be right? And should I wait to confirm with my TF100 when it gets here before draining 30% of my pool? Or should I take immediate action? Their range for CYA is 30-99. All other numbers are in line and I'm happy because I made my first adjustment successfully using the TF method, 20 oz of acid brought ny pH from 8 to 7.6. FYI I took the Clorox tabs out and will never use them again! Could these really make CYA rise that fast? Thanks
 
Eric,

I would wait until you get your test kit and then report back a full set of results... Like this...

FC
CC
pH
TA
CH
CYA

Having your CYA a little high in Texas is not all that bad... You don't really want to go above 70, but 60 would work ok...

The reason that we like to see "all" the results at once is because some things are interrelated and it is best if we know the whole story. Saying "all the other numbers are in line" just does not cut it, because your in-line might not match our in line..

Thanks for posting and hang in there...

Jim R.
 
FC 5
they don't test CC but there's a Total Available Chlorine that was 5 ("range - .2 difference from FC")
pH 7.6 (yesterday was 8, 20 oz of muriatic acid dropped it to 7.6 today)
TA 100
CH 200
CYA 70 (yesterday was 60 so they may be off readings)
 
The problem with the pucks is that the rise in CYA requires more chlorine that the tabs are not providing. The higher your CYA, the more chlorine you need. Until your kit arrives, I'd use the CYA/Chlorine chart under "Handy reference" and just use bleach to adjust FC. Make sure it's not scented or splash free. Just plain bleach.

CC is important because it tells you if the chlorine is binding to something organic in your pool. Anything over .5ppm is warning sign that there is something icky in your pool.

I never thought I'd get the hang of this, but it's not as hard as people think...You're well on your way to a trouble free pool. Good luck!
 
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If your CYA is really 70, I wouldn't bother draining any water at all. That's right in the middle of the suggested range for saltwater pools (60-80 ppm), and even if you are manually chlorinating, it's entirely manageable as long as you stay on top of things and don't ever let algae get started in your pool. It'll drop a little on it's own over time anyway, especially over the winter.





CYA that high only becomes a problem if you have to SLAM to clear up an algae outbreak, because it requires so much more chlorine to raise your FC to SLAM level (which is FC at 40% of CYA). But normal daily level is FC at 7.5-10% of CYA, and the extra CYA will actually keep you from losing as much FC each day to the sun.



But it is very important to get a test kit and take your own CYA reading. This is the single most important value to the TFP method, and sadly it's also the one that the pool stores are the worst at measuring. They can be wildly inaccurate.
 
I know he doesn't. I was just pointing out that his CYA isn't unmanageably high, even for a manually chlorinated pool.
 
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