CYA 100- need help with chlorine balance

Jul 11, 2012
17
12,600 gallon pebble tec pool. Drained in April 2016 by pool guy. Pool guy serviced with pucks until October 2017. Then we decided to take care of it on our own but were clueless so used pucks.

Fast forward to now, I have educated myself and got the Taylor kit, the good one. Anyhow, CYA is 100 and we were getting some green algae. Read about the CYA/chlorine relationship. Our CH is also 650 so honestly we intend to drain and refill come October. Right now we are backwashing frequently when the FC falls, adding water, and testing FC and adding bleach/acid. Which is how I know I will proceed once the pool water is new, since I am now educated.:p

However, my understanding from the charts is that if my CYA is 100 that my min FC is 8 and my target 11-13. Does this mean that from now on I should try to keep my level 11-13 at all times and do not let it fall under 8 under any circumstances? And shock level is 39!!! Seriously? We thought we "shocked" when we added 4 bags of cal hypo and FC only came up to 10. But pool looked sparkling. :D Few days later, back at 5. So, this week alone we went through 4 bags cal hypo plus nearly 4 gallons 10% bleach to keep FC at highest 10. But most of the time hovering 4-5. You don't have to do the math to realize this is a lot of $$$ on chlorine per week.

Question is: Am I understanding this correctly? Secondly, am I supposed to be testing my FC every night to make sure I balance it so it never falls below 8 but preferably 11-13? We have not been doing it nightly, rather every few days. It's been a time consuming learning project. ;) How often do you all test your water?

Final question: Since we plan to drain in October and start anew, does it make more sense to just to add the pucks we have until then and just throw some cal hypo in it weekly? I mean, that seems like it would be cheaper even though our whole chemistry would be askew. The CH is so high anyway at 650. My tap water is 250, FYI, in Arizona. I just feel like I've learned so much on how to manage the water ongoing but that I am kinda SOL for the rest of the season until I drain.

Any advice you can give would be very appreciated!:cool:
 
I would avoid the pucks as they will continue to make the CYA issue worse, using liquid bleach/chlorine has no adverse effects on the overall water chemistry and will generally provide the least cost method for getting chlorine in the pool.

You may want to consider a partial drain and refill to get the CYA to a more manageable number for the reminder of the season
 
A new be myself, it sounds like your CYA is way above 100 ... you can learn in poolschool how to mix it with tap water and then X2 ... just seems to me that your CYA has to be well above 100 (I found ANY bags of shock will up the CYA even more) and making your FC level under-estimated ... Algea equals a need to SLAM ... after you know the EXACT CYA reading (but lowering that is VERY important) ... being new, it sounds like ALOT of bleach/chlorine is in your future till you get your CYA down (which is sadly drain and replace some water)... I thought I saw here shock level is about 40% of CYA .. If I am wrong, I apologize ... Keep at it though and you can get control of your pool
 
A clean pool should only be using 4ppm if FC a day, so whether your target is 6ppm or 16ppm, daily FC demand should be the same.

Which Taylor kit is it, & how did you get that CYA of 100ppm? Did you check the CYA outdoors on a sunny day with your back to the sun, holding the test vial at about waist height in your shadow? As mentioned, a CYA value of 100ppm is really the upper limit of the test, and an extended test should be performed.

Whatever you decide to do, stay away from the pucks and cal-hypo. Use liquid chlorine (aka bleach) to maintain FC daily.
 
A new be myself, it sounds like your CYA is way above 100 ... you can learn in poolschool how to mix it with tap water and then X2 ... just seems to me that your CYA has to be well above 100 (I found ANY bags of shock will up the CYA even more) and making your FC level under-estimated ... Algea equals a need to SLAM ... after you know the EXACT CYA reading (but lowering that is VERY important) ... being new, it sounds like ALOT of bleach/chlorine is in your future till you get your CYA down (which is sadly drain and replace some water)... I thought I saw here shock level is about 40% of CYA .. If I am wrong, I apologize ... Keep at it though and you can get control of your pool
The OP indicated bags of shock were CalHypo, which will raise calcium, not CYA.

But,,your point about CYA is spot on. The limit of the CYA test is 100, so anytime you get 100 as a result you either need to do a diluted test to get closer to the actual number, or exchange water until the pool gets below 100 so you can accurately measure CYA.

You second point is also correct, anytime you see algae, a SLAM Process is in order.
 
Question is: Am I understanding this correctly? Secondly, am I supposed to be testing my FC every night to make sure I balance it so it never falls below 8 but preferably 11-13? We have not been doing it nightly, rather every few days. It's been a time consuming learning project. ;) How often do you all test your water?

Final question: Since we plan to drain in October and start anew, does it make more sense to just to add the pucks we have until then and just throw some cal hypo in it weekly? I mean, that seems like it would be cheaper even though our whole chemistry would be askew. The CH is so high anyway at 650. My tap water is 250, FYI, in Arizona. I just feel like I've learned so much on how to manage the water ongoing but that I am kinda SOL for the rest of the season until I drain.

Any advice you can give would be very appreciated!:cool:
As to,the first question, yes IF your CYA were 100, but I think it's much higher. A diluted test is,in order.

As to your second question, no your idea does not make any sense if your plan is to follow our methods. We teach folks to take control of their pool. To continue to toss pucks and CalHypo in there is just going to drive the CH & CYA to uncontrollable levels.

You really should conduct an Overnight Chlorine Loss Test to see if the algae is still there and if it is a SLAM Process is in order for your pool.

From this point forward your pool should be on a liquid chlorine diet, no solid forms of chlorine any more.
 
Ok, thank you for the responses. My kit is the FAS-DPD and I did use the diluted CYA test and it did come back at 90-100. I'll do the overnight chlorine loss test. So far, today, PH 7.6 and FC 5 so will be dumping in my chlorine tonight.

No one answered my question regarding where I should keep my FC. Should I be testing daily and adding enough bleach to keep it at 11? At 5 FC today it is blue and no algae that I can see. 115 degrees though, ouch.

We will keep doing the liquid chlorine or bleach. That is all we've been doing. We can't drain other than backwashing and adding because of the extreme temps. We are trying to backwash into the grass when FC drops (like tonight) and then adding a bunch of bleach afterwards and tap water to pool. Little by little this will help I guess but still we are probably looking at draining come October.

I know pucks go against everything you teach here but we have a huge jug of them and if we will not be able to drain the pool anyway till October, wouldn't it be cheaper in the end to use up our pucks and dump in extra liquid, until then. I realize the CYA will go up but it's either cut out the pucks and spend a huge fortune or add pucks and spend a small fortune. Does that make sense?

BTW...our neighbor mentioned to us his pool chemistry was out of whack too and we told him we were adding nothing but liquid chlorine now. He said he has heard that liquid chlorine is the absolute worst thing you could add to your pool because of "all the other stuff in it". ;)
 
Ok, thank you for the responses. My kit is the FAS-DPD and I did use the diluted CYA test and it did come back at 90-100.

No one answered my question regarding where I should keep my FC. Should I be testing daily and adding enough bleach to keep it at 11?
We,, if a diluted test came back at 90- 100 then your CYA is around 200. Minimum FC for 200 CYA is 15 and you should be shooting for 19 - 20 to make sure it never drops below 15.

I know pucks go against everything you teach here but we have a huge jug of them and if we will not be able to drain the pool anyway till October, wouldn't it be cheaper in the end to use up our pucks and dump in extra liquid, until then. I realize the CYA will go up but it's either cut out the pucks and spend a huge fortune or add pucks and spend a small fortune. Does that make sense?
No, because it is an upward spiral. Right now you need to keep your FC at 20, that means lots of pucks. As you use more pucks then the CYA continues up and your minimum FC goes up right along with it. Today it's 20, but more pucks it's 25, more pucks it's 30, more pucks it's 35 Understand??

BTW...our neighbor mentioned to us his pool chemistry was out of whack too and we told him we were adding nothing but liquid chlorine now. He said he has heard that liquid chlorine is the absolute worst thing you could add to your pool because of "all the other stuff in it". ;)
Now, let me get this right- The neighbor has his chemestry out of wack but you are worrying about his opinion. :confused: The other "stuff" in liquid chlorine is water and a very small amount of salt. That is what is left behind. Don't listen to your neighbor any more than you listen to the pool store "experts".
 
I have pretty much the exact same story as the OP. I am also in Az. with a CYA of 200. Pool guy keeps putting in chlorine tabs and advises a pool drain when it cools. I want to can the pool guy and take over, but am still a little leery of it all. I am going to pull the puck holders and switch to liquid, but if my FC is 3, how much bleach do I add to get my levels up to the correct levels? Not trying to hi jack thread, but almost identical story.
 
Thanks so much Tim! Forgot we didn't multiply during our little dilution test. oops. What you replied really cleared it up for me. I appreciate it immensely.

I'm off to buy a new chlorine truck......:(
 

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Autonoz...

Go here to put in your info once you get a good kit. I got FAS-DPD Taylor off Amazon.
http://www.troublefreepool.com/calc.html

Your "target" free chlorine will come from this chart, based on what your CYA level is:
Pool School - Chlorine / CYA Chart

This is how with my CYA level of 200 Tim is coming up with the min 15 FC but shoot for 19-20. Do you get it?

Dumping in all that bleach, that is what I was saying, in October I'll end up draining anyway! Grrrrrrrrrr
 
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