Only added CYA stabilizer twice since filling my pool..normal??

kb109

Bronze Supporter
Dec 24, 2018
350
Columbus, OH
My pool didn’t go up until the last week of July so I guess it’s not an “entire summer”. CYA was low upon filling the pool initially and I had to add stabilizer (sock/pantyhose trick!!) twice! Last time I added stabilizer was August 3rd. I test CYA weekly and it is always 40. Chlorine level never dips below 5.0 and the highest my CC has ever been is 0.5. Does this sound normal? I have a big jug of stabilizer just chillin in the cabinet lol. Sorry if this is a dumb question. I am not complaining but it just doesn’t seem normal lol. I use the TF-100 test kit. Thank you in advance!!
 

kb109

Bronze Supporter
Dec 24, 2018
350
Columbus, OH
My bad, August 5th was the last time I added it. CYA has been sitting pretty between 50 and 40 (it’s ALWAYS right in the middle) so I just go with 40 usually on my PoolMath app!!
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
9,695
Northern NJ
My bad, August 5th was the last time I added it. CYA has been sitting pretty between 50 and 40 (it’s ALWAYS right in the middle) so I just go with 40 usually on my PoolMath app!!
You should round CYA tests up. Your CYA IS 50. Set your FC target accordingly.
 
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mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
22,396
Laughlin, NV
If your CYA tests in the range of 30-50, set your target for what you tested. So in your case, you are testing a CYA of 50. Set your target to 50. No action needed.
 
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kb109

Bronze Supporter
Dec 24, 2018
350
Columbus, OH
If your CYA tests in the range of 30-50, set your target for what you tested. So in your case, you are testing a CYA of 50. Set your target to 50. No action needed.
Okay. I guess I shouldn’t be concerned since the stabilizer is literally keeping the water VERY stable. I used HTH stabilizer and have been using liquid bleach for a few weeks now. In the beginning I used Dichlor which I know has CYA in it. Maybe that’s why? I have not used it in a few weeks, though. All 6% liquid bleach and I only have to add a cup of bleach here n there if it’s a very sunny/hot day (it still never drops below 5 ppm but on those super hot sunny days I sometimes bump it up to 6 and it only takes about 1.5 cup to do so).
 

kb109

Bronze Supporter
Dec 24, 2018
350
Columbus, OH
I used Dichlor for a couple weeks after opening my pool (CYA was extremely low at that time and I gradually brought it up with Dichlor and stabilizer 2x via the sock method). For the past 3 weeks or so, it’s been straight liquid bleach only. I figured by now the CYA would be creeping back down a little.
 

kb109

Bronze Supporter
Dec 24, 2018
350
Columbus, OH
Any dichlor you added put CYA into the water.
Any dichlor you added put CYA into the water.
Yep I remember that. I didn’t use it for long though and it was never very much at all. I remember only using tablespoons when dosing it. I’ll have to go look at the CYA chart. I don’t really understand the point of those pucks either (never used). Don’t those raise CYA even more?
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
22,396
Laughlin, NV
Dichlor has more CYA per unit weight than trichlor (pucks).

The only way to make chlorine available in a solid product is to combine it with something. CYA is one of those somethings. Calcium is the other.
 
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kb109

Bronze Supporter
Dec 24, 2018
350
Columbus, OH
Question.... what brings CYA down? I’m not trying to bring mine down since it’s within acceptable range but I’m just curious if it decreases over time with sun/rain/etc.? I still have so much stabilizer left and haven’t used dichlor in over a month so no stabilizer has been added at all recently.