pH: how much is too much muriatic acid?

[Jacquelyn1215]

Hmm.... The CYA test is 50% pool water and 50% CYA reagent. Mix, let sit a minute, shake, then slowly pour into the measuring tube. How are you doing it?

We're following the instructions in the test kit. So I fill the bottle (#9191) to 7 ml mark with sample water, then add the R-0013 to the 14ml, cap and mix for 30 seconds, then transfer that to the small tube. Here are my photos of the test I just did again. You can see the black dot does not disappear, and that's filled all the way to the top with the full 14 ml. It does get cloudy, but does not disappear. The instructions say to add the cloudy solution "until black dot on bottom just disappears when viewed from top."

 

[Jacquelyn1215]

3 lbs if CYA stabilizer in your pool is 24 ppm. If the water in the test was cloudy but you could barely make out the dot, that sounds about right.

Okay, then maybe that's the issue - that we're not understanding the test fully (for lack of a better way of putting it). The way the instructions read to me, the black dot should disappear. It gets cloudy; it doesn't disappear.

 

[mknauss]

It should get indistinguishable as a dot. Do not stare down the tube. Glance.

CYA Testing - Further Reading

www.troublefreepool.com

 

[Bperry]

Okay, then maybe that's the issue - that we're not understanding the test fully (for lack of a better way of putting it). The way the instructions read to me, the black dot should disappear. It gets cloudy; it doesn't disappear.

In my opinion of your picture, you need more stabilizer in there as the dot isn’t even close to disappearing.

 

[IceShadow]

You have less than 30 but it could be 10 or 20. Add another 20ppm to take you up more. Let circulate a few days and test again.

 

[Dirk]

Once you complete the CYA test, the 50/50 test sample can be poured back into the squirt bottle, and you can then repeat the test. I usually do that a few times, performing the test several times, until I can assure myself I'm getting the same result. It's a great way to practice, too.

As stated, you just don't have enough CYA yet. Don't be overly concerned with what a pool guy says he did or didn't do, nor a test result he claims. I've seen 7lb bags of CYA on Amazon, and 4lbs, and 25lbs. Haven't seen three pound bags. Maybe there is such a thing, or maybe he eye-balled "about" 3 lbs of stabilizer into your pool. Who knows. Who cares.

Trust your own test results, they are telling the only story on which you can rely.

 

[Jacquelyn1215]

Re: adding the CYA (now that I've got some) how long do I need to wait after I've added muriatic acid to add the CYA? And can I continue adding muriatic acid to the pool (when recommended by Pool Math) even if the CYA hasn't yet fully dissolved in the skimmer?

 

[mknauss]

Add them. CYA is added via the sock method. The MA is added by pouring in front of a return with pump running.

 

[Dirk]

Re: adding the CYA (now that I've got some) how long do I need to wait after I've added muriatic acid to add the CYA? And can I continue adding muriatic acid to the pool (when recommended by Pool Math) even if the CYA hasn't yet fully dissolved in the skimmer?

When in doubt, wait about 15 minutes between adding different chemicals, with the pump running to circulate everything in. Not all chemicals needs this pause, but it doesn't hurt to wait and it's a good rule of thumb that's easy to remember.

As Marty points out, Muriatic and CYA acids get added using different methods, so you can do either while the other is going on. Regardless, you don't need to wait days between, I think that's what you were getting at. So if you've got CYA in a sock in front of one return, you can add your MA in front of a different return. Or if the CYA is all dissolved, and you're waiting a few days for it to show up on the CYA test, you can still add MA during that time.

Personally, I don't add CYA into the pool, only into the skimmer. Still in a sock, which I hang in the skimmer by trapping the end of the sock between the skimmer lid and the deck, so that the sock isn't laying in the bottom of the basket, and can't float out into the pool. It's sort'a hanging mid-skimmer-basket.

I burned my brand-new pebble with liquid CYA (don't use that stuff, however tempting), so I'm paranoid about having it over or in the pool. The granules are only slightly less "dangerous" in that regard, which is why I keep to the skimmer.

If you do add CYA into the skimmer, know that some of it will get trapped in the filter for a while, so it could take longer to show up on the CYA test. Also, until any that is trapped gets dissolved fully, you can't clean your filter, or you'll be washing out what CYA it's holding.

If you hang the sock in front of a return, be sure it is attached to something, such that it can't come loose and fall off and end up on the bottom. Be sure there are no holes in the sock through which granules could escape. And be sure the sock is not laying up against the side of the pool either. No touchie-touchie to anything, it needs to be suspended in the water. (You can see why I only use the skimmer for this, because, to me, it's too risky otherwise. Others have no problem doing it that way, so it's just a personal preference.)

Treat CYA as the acid that it is. Keep it off your deck. Keep it off your pool's finish. Handle and store it carefully and safely.

 

[Jacquelyn1215]

When in doubt, wait about 15 minutes between adding different chemicals, with the pump running to circulate everything in. Not all chemicals needs this pause, but it doesn't hurt to wait and it's a good rule of thumb that's easy to remember.

As Marty points out, Muriatic and CYA acids get added using different methods, so you can do either while the other is going on. Regardless, you don't need to wait days between, I think that's what you were getting at. So if you've got CYA in a sock in front of one return, you can add your MA in front of a different return. Or if the CYA is all dissolved, and you're waiting a few days for it to show up on the CYA test, you can still add MA during that time.

Personally, I don't add CYA into the pool, only into the skimmer. Still in a sock, which I hang in the skimmer by trapping the end of the sock between the skimmer lid and the deck, so that the sock isn't laying in the bottom of the basket, and can't float out into the pool. It's sort'a hanging mid-skimmer-basket.

I burned my brand-new pebble with liquid CYA (don't use that stuff, however tempting), so I'm paranoid about having it over or in the pool. The granules are only slightly less "dangerous" in that regard, which is why I keep to the skimmer.

If you do add CYA into the skimmer, know that some of it will get trapped in the filter for a while, so it could take longer to show up on the CYA test. Also, until any that is trapped gets dissolved fully, you can't clean your filter, or you'll be washing out what CYA it's holding.

If you hang the sock in front of a return, be sure it is attached to something, such that it can't come loose and fall off and end up on the bottom. Be sure there are no holes in the sock through which granules could escape. And be sure the sock is not laying up against the side of the pool either. No touchie-touchie to anything, it needs to be suspended in the water. (You can see why I only use the skimmer for this, because, to me, it's too risky otherwise. Others have no problem doing it that way, so it's just a personal preference.)

Treat CYA as the acid that it is. Keep it off your deck. Keep it off your pool's finish. Handle and store it carefully and safely.

Okay, I was planning to put the CYA in the skimmer, as well. Re: "If you do add CYA into the skimmer, know that some of it will get trapped in the filter for a while, so it could take longer to show up on the CYA test..." what is a rough idea of "longer?" Trying to understand how quickly we should see the impact of the addition.

 

[Texas Splash]

" what is a rough idea of "longer?" Trying to understand how quickly we should see the impact of the addition.

When someone pours stabilizer into the skimmer, it can take several days to a week for the granules to dissolve. By contrast, when someone uses the sock method and squeezes all the dissolved granules out, the CYA can reach its intended goal in almost 24 hours.

 

[Dirk]

I'm never in a hurry to add CYA. If I notice it's low one week, I'll add it in the skimmer, and spend some time that day squeezing the sock until it's all dissolved. Then I'll test it again in a week. Then repeat if necessary. Like Pat, I think a week aught'a do it. Except the last time, I can get it all out of the sock in about three or four "squeeze sessions." I'll just go out every hour or so, and squeeze until I'm bored, then come back later and go again.

This last time, the granules were very stubborn, and I had to let them soak overnight. Might have been a couple days. I just couldn't get them to dissolve any faster by squeezing. There were several others here that had the same issue. Several of the "different brands" on Amazon look like they all come from the same factory, so I suspect there was a bad batch making the rounds. Just mentioning it in case that happens to you.

If you're in a hurry for your CYA, there is another method I read about here that @kimkats likes. Granules in the sock, tie off the sock well, and then get in the pool with the sock, in hand. Walk around in the pool, squeezing as you go until the granules are all dissolved. I'd actually try this before hanging the sock in front of a return and leaving it unattended, if I needed to get my CYA level up quickly. At least I'd be in control and knowing where the granules are at all times! And then I'd take the rest of the afternoon off, because that would be my workout for the day!!

 

[Dirk]

Interesting. I prefer the liquid for convenience and have never had a problem with my Pebble finish. I do brush after adding it for good measure. That's the only time I brush my pool.

It's fine that you have found a method that works for you. But I think I should over-emphasize that using liquid CYA is not the recommended method here at TFP (not using it is not just my recommendation). While it is obviously possible to use it correctly and safely, because of its nature, it is quite easy to inadvertently use it incorrectly and using it incorrectly definitely can lead to damaging a pool's finish.

Putting granulated CYA into a sock, and hanging that sock in front of a return or hanging it in your skimmer are the two TFP recommended methods for adding CYA. In the skimmer is the safer method. In front of a return can dispense the CYA into your pool faster than in the skimmer.

 

[Orion7319]

Okay, then maybe that's the issue - that we're not understanding the test fully (for lack of a better way of putting it). The way the instructions read to me, the black dot should disappear. It gets cloudy; it doesn't disappear.

The CYA test is the hardest to do. I had trouble interpreting it until I picked up a bottle of CYA standard solution. Basically this is water with 50ppm CYA. You use this instead of your pool water in the test, perform the test and know that the end result is 50ppm. Once you know what the end point of the test is supposed to look like, you can run the test very easily after that.

R-7065 CYA Standard 50ppm (2oz)

tftestkits.net

 

[Jacquelyn1215]

The CYA test is the hardest to do. I had trouble interpreting it until I picked up a bottle of CYA standard solution. Basically this is water with 50ppm CYA. You use this instead of your pool water in the test, perform the test and know that the end result is 50ppm. Once you know what the end point of the test is supposed to look like, you can run the test very easily after that.

R-7065 CYA Standard 50ppm (2oz)

tftestkits.net

Ah, so the idea here is that this just shows me what the test should look like? I may need to get this. Although, happily today was the first time I did the CYA test where the water looked every so slightly cloudy. I could still see the black dot relatively clearly but there was a marked difference from before we had added the CYA.

 

[Jacquelyn1215]

UPDATE: we are making some progress with the CYA. We've been testing/maintaining our pool ourselves as of 8/21 (no longer have the pool company) and since that time we've added a total of 2# of stabilizer. We're being very conservative with it so as not to overdo it. This morning when I tested I noticed the biggest difference in that the black dot--though still visible--is definitely getting harder to see so I'm confident we're on the right track. Going to give it a few days and see what the test looks like (we added the 2nd # yesterday).

My concern is with our pH. It is not budging and is at least 8, if not higher. We have been following the recommended action from Pool Math to add muriatic acid which it feels like we've been doing almost daily at this point. I think someone had mentioned that high FC (which we initially had) can impact pH but we've got our FC down to 4.4 as of this morning but pH still high. Any suggestions/thoughts?

 

[PoolGate]

UPDATE: we are making some progress with the CYA. We've been testing/maintaining our pool ourselves as of 8/21 (no longer have the pool company) and since that time we've added a total of 2# of stabilizer. We're being very conservative with it so as not to overdo it. This morning when I tested I noticed the biggest difference in that the black dot--though still visible--is definitely getting harder to see so I'm confident we're on the right track. Going to give it a few days and see what the test looks like (we added the 2nd # yesterday).

My concern is with our pH. It is not budging and is at least 8, if not higher. We have been following the recommended action from Pool Math to add muriatic acid which it feels like we've been doing almost daily at this point. I think someone had mentioned that high FC (which we initially had) can impact pH but we've got our FC down to 4.4 as of this morning but pH still high. Any suggestions/thoughts?

2 lbs of stabilizer won't do much to your volume pool. I add it like 7 lbs at a time. 2lbs raises your CYA by 15.

I also add acid by the 1/2 gallon usually. When my pool reads 8ish I add like 1/2 gallon to get it down to 7.4. How much are you adding?

Are you using pool math for how much to add? PoolMath

Please list a full set of tests here.

 

[Jacquelyn1215]

2 lbs of stabilizer won't do much to your volume pool. I add it like 7 lbs at a time. 2lbs raises your CYA by 15.

I also add acid by the 1/2 gallon usually. When my pool reads 8ish I add like 1/2 gallon to get it down to 7.4. How much are you adding?

Are you using pool math for how much to add? PoolMath

Please list a full set of tests here.

We've been going conservative with the CYA because the last thing we want to do is too much. Paranoid maybe? Yes, probably. We are using PoolMath and adding based on the recommendations there after we test. Here's our latest logs (haven't done CH in a few days as we've had to order more reagent):

 

[PoolGate]

How much acid are you adding? I would put 32oz in every 15 minutes and re-test (pump on) until you start getting a lower reading. I put in until I see orange on the pH test solution. I know my pool now so I know how much to add without measuring. You'll get there too!

 

[PoolGate]

Also - To lower TA you reduce pH to 7.0-7.2 with acid and then aerate to increase pH.

Once you are getting a proper pH reading, work on lowering your TA. Do you have a way to aerate? Like water features?