Semi-transparent patches floating on water

We recently purchased a home with a 23,000 gallon in-ground vinyl pool (Hayward) with a sand filter. All-in-all the pool appears to be fine with crystal clear water and based on frequent testing the water chemistry appears good. The only two factors of concern chemically are that the water hardness is low (I'm working on that) and the test strips that test for such things indicate that the stabilizer is on the high side. I've never added stabilizer so I've no idea why this would be.

My primary concern is that we are getting these semi-translucent thin patches of stuff floating on the surface of the water. They have a texture to them and at first I thought they were some sort of insect eggs but clearly they are something else. They are visible only looking at the surface of the pool from an angle in the light otherwise the pool water is perfectly clear. The pool is some years old but has been well cared for by the previous owner.

Online I'm reading about white paper mold but this stuff is only on the service of the pool nothing no note when submerged.

I've been using two variants of shock normally 2 pounds at a time -- sodium dichloro-s-triazinetrione 58.2 percent and trichloro-s-triazinetrione 53.5 percent. These are probably the same thing with slightly different names.

Since the instructions say one pound to every 10k of water I've been rounding down for our 23,000 gallon pool. Maybe I should be rounding up.

Anyway, with the off chance that I've not super-chlorinated it enough I'm going to add 3 or 4 pounds tonight to really kick the water in the butt.

Any suggestions for what could be causing these floating patches?

Thanks for sharing.

Justin

Hi and welcome to the Pool Forum!

You really need to get a good kit. We don't put faith in test strips and the CYA test strips are especially bad. The kit we recommend is the Taylor K-2006 or 2006C (better buy) that you can get through the test kit link in my signature below.

We really need to know your CYA level to be able to give good advice since needed chlorine levels are based on the CYA reading.

By the way, a vinyl pool does NOT need calcium even though pool stores like to tell you that they do so they can sell you stuff to raise it!

Sigh, I've self educated myself on this pool and it's care since buying the house at the end of last November. The pool was covered all of winter with a badly torn pool cover we were afraid to remove until about the last week in February only because I had to find out what kind of mess to expect.

Fortunately the previous owner is a chemist and told me he would shock the pool the best way he knew how and that would mean using an extra strong shock formulation containing mercury.

Well that worked I guess because not one hint of algae but we had to fish out a lot of leaves at the deep end corner leaving it a bit stained. After that I've pretty much got it looking pretty damn good. I do something with the pool daily and we've spent lots of money on chemicals and supplies and yet have been in the pool a grand total of two times.

I've got THREE test kits. Two are strip based and one is the traditional, time consuming, hard to read chemical based kit (pool master basic 5). I use the chemical kit to cross check the strips in Minority Report style just to be sure what I'm seeing is sane. I'm fairly certain I'm getting lucid results for the 5 standard metrics.

Exotic stuff no. For instance CYA is not striking a chord with me. I work with two folks that used to do pool maintenance for a living and other then suggesting the clear spots floating on the surface of the water are a result of low hardness they have no idea what I'm looking at.

Happy to do yet another test kit but a kit the gives me colors to look at that are so close to looking the same is worthless to me. The chemical kit I have is like guess work because the clear pinks and yellows are so close you never feel confident you are reading it right. The strips at least give better discrete colors but I'm sure better kits are out there.

Happy to contribute to your forum if that's what it takes. I would have preferred to know it is a fee for service site before I did that. I've keyed in complete and valid information on who I am and that I'm not a spammer but I'm finding the approach taken for 'new members' both obtuse and, seriously just being frank and not meaning to offend, the new member process is a tad on the passive aggressive side. After doing everything I needed to do to get an 'account' (such as it is) there is really nothing I can do but reply to your response and visit links to pay or buy something.

I'll consider another kit and find out what CYA means as a pool care acronym I suppose. It's just this exchange has not been helpful and I had high hopes it would be.

Thanks for the response. Spending money here might be a good thing to do. Just not sure at this point.

Justin

Quote:

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Originally Posted by Jjnol

Fortunately the previous owner is a chemist and told me he would shock the pool the best way he knew how and that would mean using an extra strong shock formulation containing mercury.

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There are NOT pool sanitizers or products containing mercury. I've encountered some brain-dead chemists before, but if he really put mercury in your pool, that would certainly put him at the top of the list of crazies!

This SERIOUSLY concerns me; levels of mercury that are toxic to plants are likely to toxic to humans. You really, really need to find out EXACTLY what he put into your pool. Untill you do so -- and have verified that what he put in is not a danger to humans -- DO NOT SWIM IN IT!

I'm hoping "mercury" was a misunderstanding or a typo. If it wasn't you may not only not be able to swim; you may not be able to drain, without hiring very expensive HAZMAT remediation. Do NOT run out and drain it, in hopes you can do so without getting caught. Depending on where you drain and what he put in, you could face criminal charges if you do so!

I'm modding this in immediately, so Chem_Geek can take a look.

Quote:

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Originally Posted by Jjnol

Happy to contribute to your forum if that's what it takes. I would have preferred to know it is a fee for service site before I did that. I've keyed in complete and valid information on who I am and that I'm not a spammer but I'm finding the approach taken for 'new members' both obtuse and, seriously just being frank and not meaning to offend, the new member process is a tad on the passive aggressive side. After doing everything I needed to do to get an 'account' (such as it is) there is really nothing I can do but reply to your response and visit links to pay or buy something.

I'll consider another kit and find out what CYA means as a pool care acronym I suppose. It's just this exchange has not been helpful and I had high hopes it would be.

Thanks for the response. Spending money here might be a good thing to do. Just not sure at this point.

Justin

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Justin,
This forum is not a "fee for service site." The only reason I suggested that you get that particular kit is because it is simply the best kit out there that gives you the best information for you and us to be able to help with your pool. The forum does not sell the kit. The kit is not available anyplace locally and the link below takes you to Amazon. Although, each purchase does give a slight percentage to keeping the forum up and running, you do not have to buy the kit at all if you prefer not to and there will still be somebody here who will try and help. There is NO fee required at all on this forum. None of us that help get paid. Period. We do so simply because we like to help pool owners. As far as the new member registration process being "passive aggressive," it certainly is not meant to be. We have had a lot of issues through the years with spammers and hackers trying to cause problems for the forum and it is simply a way to try and keep the forum safe for our members.

I'm sorry that my reply was not helpful to you. I was simply trying to get some additional information to be able to better advise you. I think if you will stick around, do some reading here on the forum and especially the stickied threads at the top of each subsection of the forum and also on our sister website www.poolsolutions.com, you will learn a lot about being able to take care of your pool easily and inexpensively.

Good luck and hope you have an enjoyable swim season. :)

I seriously doubt the chemist put anything with mercury into the pool. He probably said something like adding an algicide with metals in it, maybe even saying "heavy metals" so that probably means copper. If you can still contact him, then ask him EXACTLY what was the "extra strong shock formulation containing mercury".

I don't know how accurate they are, but you can buy mercury test strips on Amazon for about $20. I think if I were in your position, I'd spend the money and be for SURE.

Yep, just checked. Copper not mercury. I was not thinking about the ramifications mercury would have. My mistake. I have ZERO concerns about the SAFTEY of the pool. It completely passes the open eyes test with no burning or irritation, no smell of chlorine at all. Test strips and old fastened mix and match kits agree the water is OK. My niece and nephew (allergic to about everything) have had zero issues swimming.

I suppose I just need to let the issue go until I come across an answer. I may have a profession water chemistry done to be sure. But with all the snow this winter, and rain (more then we've ever had in the winter in NC) there is probably not a drop of original water in that pool. We just had 4 more inches day before yesterday.

I'll stop worrying about the almost not visible floaters for now. Didn't mean to kick up all this dust. Thanks for the concern.

That's a relief. I have encountered some pretty horrible recommendations over the years by 'chemists' who were not water treatment specialists, so you really scared me. For what it's worth, mercury contamination would not necessarily have been irritating.

On the other hand, copper stains pools. If that's a concern (it doesn't bother everyone), you'll need to be cautious as you add chlorine.

Regarding your original comments:

+ CYA is one of the most critical measurements on an outdoor pool. It's very difficult to manage an outdoor pool correctly without knowing this. Most algae problems come because people do not understand that chlorine levels have to be determined based on your CYA level. Of course, some people get lucky, and do the right thing by accident. If you are naturally lucky, that's always an option.

+ Low hardness does not cause 'floaters'.

+ Dichlor and trichlor are 2 different chemicals. Both are forms of stabilized chlorine, but have somewhat different properties. The percentages you list don't correspond to undiluted products, so I'm guessing you are buying one of the diluted forms of those products. Dilutants can include borax (harmless or even helpful), magnesium sulfate (harmful to your pool), aluminum sulfate (mostly useless, but potentially harmful to concrete pools), copper sulfate (effective algaecide; effective staining agent) and so forth. You can check the "available chlorine %" to be sure. Trichlor should be 89% or higher available chlorine; dichlor should be either 56% or 61%.

+ Regarding the patches themselves, I have no idea. I can't recall ever seeing anything that would fit that description, but it doesn't sound like you could get a photograph of them. So I can't help with that.


Good luck!

Is it possible the patches are some sort of debris from the falling-apart winter cover? Sometimes plastic products seem to be multi-layer with a clear layer. It's just WAG on my part (Wild-"Artistic" Guess).

Quote:

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Originally Posted by PoolDoc

That's a relief. I have encountered some pretty horrible recommendations over the years by 'chemists' who were not water treatment specialists, so you really scared me. For what it's worth, mercury contamination would not necessarily have been irritating.

On the other hand, copper stains pools. If that's a concern (it doesn't bother everyone), you'll need to be cautious as you add chlorine.

Regarding your original comments:

+ CYA is one of the most critical measurements on an outdoor pool. It's very difficult to manage an outdoor pool correctly without knowing this. Most algae problems come because people do not understand that chlorine levels have to be determined based on your CYA level. Of course, some people get lucky, and do the right thing by accident. If you are naturally lucky, that's always an option.

+ Low hardness does not cause 'floaters'.

+ Dichlor and trichlor are 2 different chemicals. Both are forms of stabilized chlorine, but have somewhat different properties. The percentages you list don't correspond to undiluted products, so I'm guessing you are buying one of the diluted forms of those products. Dilutants can include borax (harmless or even helpful), magnesium sulfate (harmful to your pool), aluminum sulfate (mostly useless, but potentially harmful to concrete pools), copper sulfate (effective algaecide; effective staining agent) and so forth. You can check the "available chlorine %" to be sure. Trichlor should be 89% or higher available chlorine; dichlor should be either 56% or 61%.

+ Regarding the patches themselves, I have no idea. I can't recall ever seeing anything that would fit that description, but it doesn't sound like you could get a photograph of them. So I can't help with that.


Good luck!

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Thanks so much. Very enlightening. So cyanic acid is in essence the 'stabilizer' factor I've seen in the test kits. Mine was on the high side a few days ago when my water level was to the 1/4 of skimmer level. I was almost going to add water but we had a day of flash flood weather and I had to drain the pool from above the skimmer to 3/4 and now stabilizer looks OK. If anything I have to work at keeping the chlorine level up. Not seen the lock-in. I've never seen algae.

The previous owner was telling me he only used the copper based shock in the winter because it works very differently to create free chlorine then the other treatments. And seriously other then these little filmy patches that I've seen floating on the surface, appearance and chemistry has never been seriously out of whack since I got it cleaned up after winter.

BTW, this evening I looked and they were gone. All sucked into the skimmer. I shocked it last night.

If I can get the right light and angle I'll use the macro lens on my digital SLR to see if I can get a photo of the translucent floaters as they get sucked into the skimmer. They do come and go. It may just be some form of pollen for all I know.

It's good to know it's not the hardness. I'm not going to play with adding calcium as long as it won't cause a problem for my vinyl surfaces. Someone told me having too soft water would dry out my vinyl which did not make sense to me.

The stuff I use for shock come in 1lb packets from PoolTime and seem to work well.

And concerning the CYA it's my understanding that the tablets I put in my floating dispenser may actually be adding that to the pool. I'll check and if so try not to over do that. I thought for a while the more chlorine the better -- clearly not so.

And again thanks for the helpful reply.

Justin

Quote:

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Originally Posted by Jjnol

Thanks so much. Very enlightening. So cyanic acid is in essence the 'stabilizer' factor I've seen in the test kits. Mine was on the high side a few days ago when my water level was to the 1/4 of skimmer level. I was almost going to add water but we had a day of flash flood weather and I had to drain the pool from above the skimmer to 3/4 and now stabilizer looks OK. If anything I have to work at keeping the chlorine level up. Not seen the lock-in. I've never seen algae.

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Justin, what is your CYA level now? It's actually Cyanuric or Isocyanuric acid. Yes it's stabilizer and it prevents chlorine from breaking down too fast, especially in direct sun where UV can break chlorine down in as little as 15 minutes. But it's a two edged sword as you need higher levels of chlorine to maintain sanitary water...see our "Best Guess Table" for the levels of free chlorine needed for various levels of CYA.

Quote:

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The previous owner was telling me he only used the copper based shock in the winter because it works very differently to create free chlorine then the other treatments. And seriously other then these little filmy patches that I've seen floating on the surface, appearance and chemistry has never been seriously out of whack since I got it cleaned up after winter.

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I have no idea what he was thinking. Copper kills algae, but it doesn't sanitize your pool. If the copper kills the algae, you don't need chlorine to do it, "saving" your chlorine for sanitation. So the theory goes. But copper doesn't create Free Chlorine.

Quote:

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BTW, this evening I looked and they were gone. All sucked into the skimmer. I shocked it last night.

If I can get the right light and angle I'll use the macro lens on my digital SLR to see if I can get a photo of the translucent floaters as they get sucked into the skimmer. They do come and go. It may just be some form of pollen for all I know.

It's good to know it's not the hardness. I'm not going to play with adding calcium as long as it won't cause a problem for my vinyl surfaces. Someone told me having too soft water would dry out my vinyl which did not make sense to me.

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Makes no sense to us, either. Your instincts are right on. Calcium is to prevent mortar, plaster and concrete from having their calcium leeched out. Period.

Quote:

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The stuff I use for shock come in 1lb packets from PoolTime and seem to work well.

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What does it say is in it? Hard to tell if it's good or bad just from a name.

Quote:

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And concerning the CYA it's my understanding that the tablets I put in my floating dispenser may actually be adding that to the pool. I'll check and if so try not to over do that. I thought for a while the more chlorine the better -- clearly not so.

And again thanks for the helpful reply.

Justin

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Chlorine tablets are almost always Tri-Chor tablets, and, yes, they do add CYA to your water: For every 10ppm of Free Chlorine they add 6ppm of CYA. That's good when your CYA is low, bad when it's high. They also are very acid and can and will lower your pH. Be very careful though: If they say "Double Acting" or anything by 99% tri-chlor, they are probably adding MORE copper to your water. We recommend against that.

More chlorine generally IS better, but at very high levels it can bleach liners and bathing suits...HOWEVER, if your CYA level is high, the appropriate maintenance level of Free Chlorine probably won't do that.

Quote:

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Originally Posted by Watermom

Justin,
This forum is not a "fee for service site." The only reason I suggested that you get that particular kit is because it is simply the best kit out there that gives you the best information for you and us to be able to help with your pool. The forum does not sell the kit. The kit is not available anyplace locally and the link below takes you to Amazon. Although, each purchase does give a slight percentage to keeping the forum up and running, you do not have to buy the kit at all if you prefer not to and there will still be somebody here who will try and help. There is NO fee required at all on this forum. None of us that help get paid. Period. We do so simply because we like to help pool owners. As far as the new member registration process being "passive aggressive," it certainly is not meant to be. We have had a lot of issues through the years with spammers and hackers trying to cause problems for the forum and it is simply a way to try and keep the forum safe for our members.

I'm sorry that my reply was not helpful to you. I was simply trying to get some additional information to be able to better advise you. I think if you will stick around, do some reading here on the forum and especially the stickied threads at the top of each subsection of the forum and also on our sister website www.poolsolutions.com, you will learn a lot about being able to take care of your pool easily and inexpensively.

Good luck and hope you have an enjoyable swim season. :)

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I appreciate the helpful and measured reply to my somewhat frustrated post regarding how the site is set up for new members. In addition to yourself, PoolDoc and others have provided helpful answers. It's clear the group of users on the site are sincere and knowledgeable. I plan to pay the subscription fee today.

I'm going to order the Taylor Cyanuric testing kit and the pint refill today as well. I do have a regent-based chemical kit that's new and, based on its packaging, may be the smaller Taylor kit with another name slapped on it.

I've not been using it much since it's just plan hard to use and I don't find the color reference scale easy to read. You would think they could come up with test kits that give a more delineated color scale so after you've done the mixing, swirling, shaking and squinting you get the sense that the color match you make is the right one. The scales on these kits are so close to the same color that I never really feel like I've interpreted the test correctly. This is where (right or wrong) the strips do a better job. I've not yet had the two types of tests violently disagree with each other. I admit I don't do both every time relying I suppose on having gotten good results and outcomes with the pool itself. BTW, the floating patches pretty much went away yesterday. I think they may be related to a type of late season pollen we have in this area. If the floaters come back I will post a photo. The clarity of the pool water is outstanding (spectacular even) with almost no sediment accumulation over days and weeks of not vacuuming.

NC is right under one of the weather jet streams and so our weather tends to turn on a dime from one extreme to another (dry/cold or warm/wet) and this past winter was off the charts wet and cold and we've had the coolest spring/summer I can remember. So the pollen load has been unusual.

Just so the forum gets credit for my purchases I assume I need to make the jump to Amazon from one of your links so the URL has the correct imbedded information? Please advise.

Thanks again for the polite an measured response. I'm sure you deal with all types.

Justin 😊

Quote:

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Originally Posted by CarlD

Justin, what is your CYA level now? It's actually Cyanuric or Isocyanuric acid. Yes it's stabilizer and it prevents chlorine from breaking down too fast, especially in direct sun where UV can break chlorine down in as little as 15 minutes. But it's a two edged sword as you need higher levels of chlorine to maintain sanitary water...see our "Best Guess Table" for the levels of free chlorine needed for various levels of CYA.



I have no idea what he was thinking. Copper kills algae, but it doesn't sanitize your pool. If the copper kills the algae, you don't need chlorine to do it, "saving" your chlorine for sanitation. So the theory goes. But copper doesn't create Free Chlorine.




Makes no sense to us, either. Your instincts are right on. Calcium is to prevent mortar, plaster and concrete from having their calcium leeched out. Period.




What does it say is in it? Hard to tell if it's good or bad just from a name.



Chlorine tablets are almost always Tri-Chor tablets, and, yes, they do add CYA to your water: For every 10ppm of Free Chlorine they add 6ppm of CYA. That's good when your CYA is low, bad when it's high. They also are very acid and can and will lower your pH. Be very careful though: If they say "Double Acting" or anything by 99% tri-chlor, they are probably adding MORE copper to your water. We recommend against that.

More chlorine generally IS better, but at very high levels it can bleach liners and bathing suits...HOWEVER, if your CYA level is high, the appropriate maintenance level of Free Chlorine probably won't do that.

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CARL, awesome information. Thank you thank you. And in fairness to the previous owner of the house the conversation on copper and shocking was last November when we were doing the home inspection. Goodness knows, considering my ignorance then, what he actually said. He is a bio chemist working for Glaxo Smith-Cline pharmaceuticals just a mile from here and I'm sure he knows his stuff.

As to the tablets I am going to monitor their use and start following the directions for the size of my pool. I think it calls for three in one floater and I've just been loading the floating duck up. I don't think I've hurt anything yet but with that I'm on a bad road.

All this is very good to know. THANKS��

Justin,
Just some additional information about the Taylor K2006 kit. It does NOT use color matching, so you might like it much better than the one you are currently using. You add a powder to turn a sample of water pink and then add drops of a different reagent, counting drops, until the sample turns clear. That is how your chlorine reading is determined and thus you don't have to do any color matching at all. Plus, with the K2006, you can read chlorine levels up to around 50ppm whereas with most other kits, 5ppm is as high as can be distinguished.

In regards to using the trichlor tabs, if you haven't added any yet, I would wait to do so until you find out what your CYA reading is. If you find that it is already really high (which we commonly see here on the forum), then you would probably do best to use an unstabilized form of chlorine instead of trichlor or dichlor.

(And, yes, for the forum to get a percentage, you do need to access Amazon through the link in either my or PoolDoc's signature. In fact, ANY purchases people make can earn money for the forum if you start in those links. From there you can navigate to any products that Amazon sells --- doesn't even have to be pool stuff -- and the forum still earns a little. It really helps us to be able to keep the forum afloat and online to be able to help people with their pools. So, we really appreciate when people use our link whenever they are going to order stuff from Amazon. Thanks!)

I will do it. Yeah the Taylor kit does sound better. I'm a software engineer and work for Apple and wish there were an electronic way to do all this testing. Frequency of testing for the normal owner of a pool is probably directly proportional to how easy it is to do. I sense there is an immense dislike for the litmus strips and I don't doubt they are not as precise but what they loose in exactness they make up for in ease of use. And I'm not making it up I've never gotten a reading from the regent-based kit that was at complete odds with the test slivers I've been using. The fruit of the tree has been pretty good in my case so I've not questioned the readings I'm getting.

Still I will upgrade the kit. It seems prudent and I'm pretty pedantic so it fits.

I'm pulling the floater from the pool today. It's still on the mildly chilly side here in North Carolina (very uncharacteristic for this time of year) so we've not been in the pool much so having the dispensers in there all the time considering I shock once a week is probably not needed.

So hopefully an easy question: The pool is 23,000 gallons and the shock calls for 1 pound per 10,000. I've been rounding down (the stuff is pricy). The readings after a night time shock with the filter running all night is as high as you would expect it to be for super chlorination so I assume rounding down is OK?

Justin :o)

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Originally Posted by Jjnol

I'm a software engineer and work for Apple and wish there were an electronic way to do all this testing.

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You, and a million other people. Unfortunately, the 'wet-end' technology for turning chemical conditions into PRECISE electrical signals is 50+ years old, and has not improved. The anitique IT acronym "GIGO" (Garbage in; garbage out!) applies directly here: no amount of digital technology on the 'dry end' can make up for randomly bad data originating on the 'wet end'!

But, where there's a desire to buy, there will be a willingness to sell 'snake oil'. And, until the 'wet end' tech advances, that's about all that digital pool sensing and control will be.

Meanwhile, lots of companies are separating lots of pool owners, from lots of money, by selling them lots of 'snake oil' tech.

Quote:

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Originally Posted by Jjnol

Frequency of testing for the normal owner of a pool is probably directly proportional to how easy it is to do. I sense there is an immense dislike for the litmus strips and I don't doubt they are not as precise but what they lose in exactness they make up for in ease of use.

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That is precisely what they don't do: they don't make up for it at all. "GIGO" applies here, too. Bad data from 'guess-strips' ==> bad treatment decisions ==> bad pool conditions ==> unhappiness with how nasty the pool is, and how hard pool care is.

With experience, testing frequency will be very low. I'd be embarrassed to tell you the testing frequency I follow on very large commercial pools, once I've serviced them for years. (Chlorine levels ARE tested 4x or more per day, though!) Once you've learned how to care for your pool, you probably won't need to test CH or CYA more than 3x per year. If you have a vinyl pool and no heater . . . you probably won't test TA at all, unless you have some indication of an issue. You'll ALWAYS need to test chlorine 3x per week, and pH at least 1x per week, but 2 of those events can usually be done with an OTO/phenol red kit (2 minutes!)

BUT . . . if you want to have an enjoyable, relatively inexpensive and trouble free pool THIS summer, you're going to need to test more than that, and to test accurately.

Justin,
I actually know the area where you live reasonably well, having lived in Carrboro, and still having family in the area. But I did move away a long time ago--a lifetime! But I have been back as recently as last June. I loved living in the area but the population has exploded over 30 years now.

You get a full 2 months more of pool season than we do--a full 5 months!

Quote:

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Originally Posted by PoolDoc

You, and a million other people. Unfortunately, the 'wet-end' technology for turning chemical conditions into PRECISE electrical signals is 50+ years old, and has not improved. The anitique IT acronym "GIGO" (Garbage in; garbage out!) applies directly here: no amount of digital technology on the 'dry end' can make up for randomly bad data originating on the 'wet end'!

But, where there's a desire to buy, there will be a willingness to sell 'snake oil'. And, until the 'wet end' tech advances, that's about all that digital pool sensing and control will be.

Meanwhile, lots of companies are separating lots of pool owners, from lots of money, by selling them lots of 'snake oil' tech.



That is precisely what they don't do: they don't make up for it at all. "GIGO" applies here, too. Bad data from 'guess-strips' ==> bad treatment decisions ==> bad pool conditions ==> unhappiness with how nasty the pool is, and how hard pool care is.

With experience, testing frequency will be very low. I'd be embarrassed to tell you the testing frequency I follow on very large commercial pools, once I've serviced them for years. (Chlorine levels ARE tested 4x or more per day, though!) Once you've learned how to care for your pool, you probably won't need to test CH or CYA more than 3x per year. If you have a vinyl pool and no heater . . . you probably won't test TA at all, unless you have some indication of an issue. You'll ALWAYS need to test chlorine 3x per week, and pH at least 1x per week, but 2 of those events can usually be done with an OTO/phenol red kit (2 minutes!)

BUT . . . if you want to have an enjoyable, relatively inexpensive and trouble free pool THIS summer, you're going to need to test more than that, and to test accurately.

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Yes I've seen a few "electronic testers" for certain pool chemical metrics. Good to know good they are not. So all this discussion about testing and kits and how best to do it forced me to pull out the regent based kit again and go through all the tests. Alarmingly I found that according to the alkalinity titration test (which I performed twice) my alkalinity is at 150 (took 15 drops to make the pale blue go clear). It is supposed to be 80 to 120. So I went to Taylor's site and looked for relationship between alkalinity and Cyanuric acid and found this link https://www.taylortechnologies.com/C...SP?ContentID=5.

I don't have a CYA test kit yet but if I'm reading the Taylor page correctly a big part of that 150 could be attributable to Cyanuric acid levels in my pool. Sort of a shadow effect. So then the question becomes is my alkalinty really that high because the strips don't say that (both versions). Seems the straight forward TA test does not account for a Cyanuric byproduct titrating out cumulatively with the alkaline.

Still at 150 that's high so will probably need to get that down just a little until the CYA kit gets here. Yet the pool looks and acts fine. Even the floaters are gone.

The "total alkalinity" test is just that; not a "carbonate alkalinity" test. In water treatment, "alkalinity" is a measure of a solution's resistance to pH change, over a specific range. As long as it's not massively high or zero, a non-ideal alkalinity is not a crisis.

Regarding electronic testing . . . until there are major advances in the part of the test that gets wet, those tests have little value to most pool owners. They are used in labs, because they are potentially very, very accurate, but achieving that accuracy requires frequent and complicated calibration to match the electronics to the signals. If you think messing around with a drop-based (titration) test kit is a pain, you ought to try double buffer electrode and temperature calibration, or maintaining and calibrating against other lab-standard solutions.

Quote:

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Originally Posted by PoolDoc

If you think messing around with a drop-based (titration) test kit is a pain, you ought to try double buffer electrode and temperature calibration, or maintaining and calibrating against other lab-standard solutions.

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Would there be any time left over to swim????? :)