Chlorine and PolyQuat 60 compatibility or incompatibility

jmb

Member
May 26, 2011
20
Windsor Ontario Canada;SW Ontario near Detroit, MI
Pool Size
36000
Surface
Vinyl
Chlorine
Liquid Chlorine
Thank you for the recent you tube video about closing pools for winter freezing conditions; Winterize Your Pool With Trouble Free Pool on Aug 28, 2021.

We are preparing to close our pool in Southern Ontario. We use a mesh cover; our CYA is 40; we have balanced the pool water, then slammed the pool (raised chlorine to shock level) and brushed the walls and bottom.

We have always closed the pool mid September and opened early to mid June depending on weather. In our area we are starting to get windy stormy fall conditions. Our pool is surrounded by gardens and trees. A lot of debris will soon start to collect in the pool requiring fairly extensive daily maintenance if left open. Additionally we do not use a heater and the water temperatures are getting too cold to enjoy swimming. I am aware of the advantage of opening when the pool temperatures drop below 60 degrees and this is not feasible for us.

I am also aware of the some of advantages of the solid cover versus a mesh cover but for us the advantages of the mesh cover outweigh the disadvantages of the solid cover.

When we close the pool we use a combination of slamming the pool, brushing and cleaning very well and letting the chlorine drift back down before adding PolyQuat 60. We generally let the chlorine drift to about 1/2 way between the high target level and the shock level based on our CYA level. (We only use PolyQuat 60 for pool closing)

From what I understand about the Chlorine / PolyQuat 60 compatibility issue, I suspect that the chlorine level perhaps should not be higher than your chlorine target level based on your CYA; and, this is a point I am trying to clarify.

Overall our method has worked fairly well for us. When we open the pool there is some debris at the bottom (a film of sand, pollen etc) from using a mesh cover. The water is not crystal clear but we can see the bottom of the pool. We can clean the pool fairly quickly with 2 to 3 days of slamming; and, a couple of good vacuums and brushing before we start using our Polaris pool cleaner. This year we installed a Stenner Pump which has greatly facilitated adding daily liquid chlorine. Pool has been crystal clear all summer.

We would like to tweak the closing technique regarding our chemical balancing a bit to determine what ppm chlorine should we let the chlorine drift down to before we add PolyQuat 60?
We would like to better understand what happens to the algaecide and/or chlorine that we have added. The combination seems like it must be doing some good as the chlorine levels are essentially non existent when we open; but, the water is not too bad in clarity.

Although we would like to tweak our closing procedure as best as possible I am not sure we can expect much better results given that we are using a mesh cover and we are closing and opening under less than ideal conditions.

In summary;
1. How much chlorine is too much to prevent PolyQuat 60 algaecide from working?
2. Once the chlorine drops a bit after closing does the algaecide then become active or unblocked?
3. Does the chlorine completely destroy the algaecide or just partly; and, does the answer to this question depend on what the chlorine level was when you added the PolyQuat 60?
4. Does PolyQuat 60 lower free chlorine; and, if so, does it lower it to a certain amount or completely?
4. I would like to have a better understanding of the mechanics of how the chlorine and PolyQuat 60 interact with each other to determine the proper level of chlorine to get the most effective benefit of both chemicals when closing the pool.
5. Based on the conditions discussed about what is the ideal pH for closing the pool.

Thank you.
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
Jun 22, 2014
33,620
Texas, San Antonio/Marion, South-Central Area
Pool Size
17888
Surface
Fiberglass
Chlorine
Salt Water Generator
SWG Type
CircuPool RJ-45 Plus
We could really get into some chemistry on this one, but I'll start off by providing you with some previous discussions below and a few basic reminders.

1. You keep your pool closed for about nine months. That's an extremely long period for any closing process, and expectations of having pristine/clear water are probably just a bit too high. I think for are fortunate to only have a 2-3 day clearing period.
2. The PoolMath APP (Effects of Adding) will tell you what impact adding x-amount of Poly 60 will have on your other levels. As you can imagine, it depends on your current FC and how much Poly you add.
3. The ideal pH for you is probably anywhere in the 7.6-7.8 range. With a vinyl pool, your biggest concern is not having a really low pH which could impact the vinyl. PH climbs in cold water, but should settle in the 8.2 - 8.5 range.
4. With the pool closed for so long, it might be to your advantage to simply pull the mesh cover back once or twice, drop a small submersible pump in there along with some chlorine to let is mix a bit.



 
  • Like
Reactions: jmb

skimmerswimmer

Well-known member
Jul 30, 2013
487
Long Island, NY
I used to use polyquat for closing but I no longer do. I close in mid-October with chlorine near SLAM level and open in early April. Water temps well below 60 degrees help a lot. The trick for me is to leave two floating chlorinators on a line strung across the pool under the cover, each containing 4 pucks. These will slowly dissolve over the winter months and provide residual chlorine. I also have a mesh cover and a few times over the winter when the water isn't frozen, I pull up a corner and drop in the robot to clear out residual leaves, dirt, worms and other debris to keep chlorine demand low. I always open to a nice and clear pool.
 
  • Like
Reactions: jmb

wireform

Silver Supporter
In The Industry
Aug 15, 2017
3,116
Spring Valley, NY
I used to use polyquat for closing but I no longer do. I close in mid-October with chlorine near SLAM level and open in early April. Water temps well below 60 degrees help a lot. The trick for me is to leave two floating chlorinators on a line strung across the pool under the cover, each containing 4 pucks. These will slowly dissolve over the winter months and provide residual chlorine. I also have a mesh cover and a few times over the winter when the water isn't frozen, I pull up a corner and drop in the robot to clear out residual leaves, dirt, worms and other debris to keep chlorine demand low. I always open to a nice and clear pool.
Like your idea but I'm afraid not being able to see the floaters and they get damaged during a freeze can lend itself to a new problem that if it falls apart after a thaw and they drop to the floor sitting on the liner will do a number.
 

jmb

Member
May 26, 2011
20
Windsor Ontario Canada;SW Ontario near Detroit, MI
Pool Size
36000
Surface
Vinyl
Chlorine
Liquid Chlorine
I used to use polyquat for closing but I no longer do. I close in mid-October with chlorine near SLAM level and open in early April. Water temps well below 60 degrees help a lot. The trick for me is to leave two floating chlorinators on a line strung across the pool under the cover, each containing 4 pucks. These will slowly dissolve over the winter months and provide residual chlorine. I also have a mesh cover and a few times over the winter when the water isn't frozen, I pull up a corner and drop in the robot to clear out residual leaves, dirt, worms and other debris to keep chlorine demand low. I always open to a nice and clear pool.
Interesting Idea about hanging the floating chlorinators. I would prefer to close with water temperatures closer to 60 and open earlier but with our conditions this is not feasible. We would spend a lot more time and money doing this than what we are currently doing. I believe in our circumstances the polyquat is definitely helping as the pool is not too bad when we open. I am reading more posts on how to best methods for dispensing the polyquat and about the FC and polyquat chemistry interaction and I am starting to understand this much better now.
 

1Sammy

In The Industry
Jul 20, 2017
438
Windsor, Ontario. Canada
jmb. Put your safety cover on now and leave everything else as it is. Cut back huge on pump time and drop your stenner timer back also, maybe off every second or third day. Come November undo the straps enough to get at your returns and skimmer so you can blow your lines and winterize. You can also let your Polaris do a few laps. I made the mistake of buying a mesh safety cover 27 years ago BUT the last 15 years i have done as mentioned above and then i add a tarp cover which is solid. It lays on the safety cover and rides up and down with the safety cover as snow comes and goes. It is held in place with 1/4" rope from the Dollar Store running back and forth across the top and ties to the spring straps. You can also weave a rope in the grommets along the outer edge of the tarp . Takes minutes to add this plus rope time. I have a 1HP pump hanging full time just above the center of the tarp. When there is water on the top i just lower the pump, run for a few minutes, unplug and lift off by tightening the rope by moving it to another hook in the fence.
Chorine lost is VERY low, water is just as it was when you closed with zero clean up needed.
 
  • Like
Reactions: jmb

jmb

Member
May 26, 2011
20
Windsor Ontario Canada;SW Ontario near Detroit, MI
Pool Size
36000
Surface
Vinyl
Chlorine
Liquid Chlorine
We could really get into some chemistry on this one, but I'll start off by providing you with some previous discussions below and a few basic reminders.

1. You keep your pool closed for about nine months. That's an extremely long period for any closing process, and expectations of having pristine/clear water are probably just a bit too high. I think for are fortunate to only have a 2-3 day clearing period.
2. The PoolMath APP (Effects of Adding) will tell you what impact adding x-amount of Poly 60 will have on your other levels. As you can imagine, it depends on your current FC and how much Poly you add.
3. The ideal pH for you is probably anywhere in the 7.6-7.8 range. With a vinyl pool, your biggest concern is not having a really low pH which could impact the vinyl. PH climbs in cold water, but should settle in the 8.2 - 8.5 range.
4. With the pool closed for so long, it might be to your advantage to simply pull the mesh cover back once or twice, drop a small submersible pump in there along with some chlorine to let is mix a bit.



Thank you so much for your reply. I agree that we are very fortunate to have a short cleaning period. It is much better the past few years since we have been following the TFP closing suggestions which can be very different depending on your environment. I believe in our circumstances the polyquat is definitely helping as the pool is not too bad when we open. I believe we close too early to not use it. I am reading more posts for the best methods for dispensing the polyquat and about the FC and polyquat chemistry interaction. I am starting to understand this much better now. Thank you for the links sent. For our circumstances the process of slamming and then letting the FC drift back to a level between target and shock has been working fairly well. I have been using pool math app for a couple of years now and it is so much easier to manage the pool and control chemical additions. For some reason I had not thought of checking the app to determine the effect of the Polyquat. Great suggestion and I am so happy you mentioned it. I will definitely use it for this closing. The idea of adding chlorine with a small sumbersible pump is feasible and we will consider it.

Someone else mentioned throwing in the Polaris cleaning robot a couple of times to clear the debris from the bottom of the pool to lower the demand for chlorine. This also sounds like a good idea, but, I am a bit concerned about not being able to see what it is picking up. This is only our 2nd season with our Polaris cleaner which has been one of our best purchases. It is easy to use and works great it . When we open the pool we generally hand vacuum the pool 2 to 4 times to get the worst of the debris up before we start using the Polaris pool cleaner. Maybe the Polaris can handle the initial clean up. We did not use it for 2 reasons. We did not want to contaminate it with algae that may be in the pool and we were concerned about putting too much stress on it.

The primary seasonal service we use the pool store for is closing the pool as we have not yet developed the confidence to blow out our own lines. Before I learned about TFP and doing our own chemical additions they used to just throw in 10 liters of chlorine and the 32 ounces (.946 Liters) polyquat on the day of closing without any mixing and it would take a lot more time, effort, and money on chlorine to clean the water.
 
  • Like
Reactions: Texas Splash

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
Jun 22, 2014
33,620
Texas, San Antonio/Marion, South-Central Area
Pool Size
17888
Surface
Fiberglass
Chlorine
Salt Water Generator
SWG Type
CircuPool RJ-45 Plus
Sounds like you are learning quite a bit already. I wouldn't be surprised if you decided to open and close after this winter. Lots of folks here to help if you have questions.
 

jmb

Member
May 26, 2011
20
Windsor Ontario Canada;SW Ontario near Detroit, MI
Pool Size
36000
Surface
Vinyl
Chlorine
Liquid Chlorine
Sounds like you are learning quite a bit already. I wouldn't be surprised if you decided to open and close after this winter. Lots of folks here to help if you have questions.
We always open the pool ourselves. The only thing we are not comfortable with is blowing the lines but I have seen many good explanations and watched the recent TFP pool video about this.
Curious, I just checked the Pool Math App to learn about the effects of adding polyquat 60.
The answer generated was something like "no changes detected"
It only asked me for the amount of polyquat I was going to add and I entered 1 Liter. There was no place to enter what my FC level was prior to adding. Also I am using polyquat 60 but I have seen it sold in more diluted amounts; if the app were working for me is it assuming you are using polyquat 60 since that is the one recommended? From what I can see the articles discussing polyquat seem to be based on using Polyquat 60.
Am I perhaps missing something or is the app just not set up to generate an answer?

After reading the links you sent I have a few questions:
1. Is the reason for adding the Polyquat 60 when the FC is 10 or less to prevent the polyquat from getting oxidized by the chlorine if the chlorine were to be at a higher level.
2. Based on the above explanation; Do you know if the Pool Math App should be working to provide the effects of adding Polyquat; and if so, what I might be doing wrong?
3. I will check my free chlorine levels before and after adding polyquat 60. Am I correct in understanding that if the free chlorine drops below target after pumping through the Polyquat 60 that I should then raise the free chlorine level back up to target before closing; if so,
4. Is there a period of time I should wait after adding the Polyquat 60 before adding chlorine should it be necessary? (I have read about about adjusting pH after adding polyquat; in my experience from past years my pH when opening has not been too much of an issue)
 

Enjoying this content?

Support TFP with a donation.

Give Support

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
Jun 22, 2014
33,620
Texas, San Antonio/Marion, South-Central Area
Pool Size
17888
Surface
Fiberglass
Chlorine
Salt Water Generator
SWG Type
CircuPool RJ-45 Plus
I think you are correct in that the APP was based on Poly 60 and not the weaker version (Poly 40 I think). For your questions:
1 - Correct
2 - We need to look into this a bit more. @Leebo, is the Polyquat selection functioning? No matter what I enter there are no changes. Perhaps that is because technically Poly doesn't change products, other products (chlorine) change Poly?
3 & 4 - Ideally, take your water up to about SLAM (FC) level first. Our closing article says 2-3 days, but you might start about 5 - 7 days prior to closing. After that 5-7 day times frame, the FC should have fallen a bit. Go ahead and add the Poly 60 at that time. It is possible that your water might be so cold, coupled with the lack of intense sun, that the FC might still be high. At that point you can still add the Poly knowing the chlorine my oxidize some of it, or just skip the Poly. The high chlorine level and pre-cleaning should leave your water with next to no organic activity.
 
Thread Status
Hello , This is an inactive thread. Any new postings here are unlikely to be seen or responded to by other members. You will get much more visibility by Starting A New Thread