...other things that claim to reduce chlorine usage?

[terryc]

Very good. Thank you chem geek. Sorry I just didn't react well to the blanket do what we say with no backup. Felt like I was a the pool store honestly. Thanks for the in depth explanation and links. I do have a lot of phosphates in the pool but won't try adding more. I don't want to have the FC that high on a regular basis so about a 1/3 less on the chart should work for me and I'll have to figure out a way to keep my CYA down.

So you think that likely there is no adverse affects to prolonged exposure to chlorine at the 7 or 8 ppm recommended for a CYA of 60-80 or would you advocate just keeping CYA at 30 or below where possible.

Lol at getting my first thread sent to the "deep end".

 

[duraleigh]

For newbies stumbling across this thread, please do not place ANY merit in what terryc has posted. It seems he is here for the sake of the argument rather than taking an objective look at what we teach. The procedures we use have been proven to work in thousands and thousands of pools.....year after year without exception.

Borates are an optional chemical that may result in slower pH movement, perhaps a mild algaecide, but it is not the "magic bullet" that terryc wants it to be.

terryc has apparently since deleted it, but in earlier post, freely admitted that he was too cheap to buy a test kit and too lazy to manage his pool in a reasonable approach. To me, that removes any validity to his expertise on the effects and use of borates.

I will let this thread continue to some conclusion because there are so many kind and patient responders who are willing to help and the discussion has remained polite. However, I suspect that terryc is not here for the help.

 

[harleysilo]

Yes that is referring only to shock levels.

The answer to the question regarding lower FC levels in general for a SWCG pool, that has to do with the super-chlorination going on in the SWG and i think the addition of chlorine throughout your pump run time helps some too versus one daily does. Salt doesn't do anything for sanitation, and borates are a mild algecide, but they don't sanitize either.

Chlorine kills algae but more importantly it kills all the nasty that can make you sick.

Well I read all of this thread and can now say my original post appears to be a simple summary of everything, terry have you read up on the reaction occurring inside SWG's? The resulting PH rise was killing me till I added 50 of borates. Now all is well.

 

[Donldson]

Warning: Total Honesty Ahead

Sorry I just didn't react well to the blanket do what we say with no backup. Felt like I was a the pool store honestly

Have you read the Pool School? How about the 24 page discussion on adding borates that the pool school links to? Do you believe that nobody has come up with these same ideas you have? Since Ben Powell created the "best guess" FC/CYA chart it has been discussed to death. Since chemgeek refined it people have been discussing it and swearing up and down that they run a perfect pool with less chlorine. I am not saying you aren't making some valid arguments, though chemgeek proved they aren't all valid, I am saying you are not the first person to make them. People come here all the time, see the chart and think "That's too high, I can figure out a better way." Fine, hope it works for you, but don't tell the tens of thousands of us who have been running those "high" FC levels for years and noticing ZERO adverse effects that we are wrong.

Personally, for me, if I come up to a minefield and see footprints that lead to the other side, I am going to follow those.

 

[terryc]

Sorry if I seem unappreciative of the site. It is far from the truth, this is a great site with lots of info. I did not delete anything. I must have docents my laziness and cheapness in another thread. Now I don't say that to mean I won't do work or spend money, I just don't like to do it unless it is absolutely necessary. I guess maybe I'm a BBB ideology purist. . I probably am a bit argumentative so Dave got me there. I don't think that makes me any less objective ( probably makes me more objective ). I'm willing to follow the methods here but not blindly nor immediately.

My apparently sacreligious post did get me want I want. An excellent post from chemgeek correcting all the misinformation that I freely but inadvertently gave along with papers, equations, and opinion that was helpful and interesting. Also in case you missed it he also provided his opinion based on personal examples of how he thought the FC/CYA could change with 50 ppm of borates.

I think that this was a good example of a still skeptical newbie giving and getting good feedback. People can respectfully disagree with each other and that is how great compromises come out. There are a lot that blindly follow and apparently get a little upset when someone questions the methods used here or tries to provide there personal experience.

I'm probably going to post a couple of other question on the other crud that I bought from Leslie's originally. Don't worry though I'm coming around to tbe Bbb method.

 

[duraleigh]

Nice post. :lol: Here's still a point of contention that requires clarification.....

There are a lot that blindly follow and apparently get a little upset when someone questions the methods....

That's simply incorrect. Folks here are anything but blind and have taken the trouble to learn and understand how to manage their pools with remarkable success....nobody's blind.....quite the opposite.

Challenging what we know to be bullet proof science and remarkably consistent outcomes with faulty logic and misconceptions is what causes the somewhat emotional challenges you are getting.

We've hashed this stuff out over and over for 10+ years....we know what we are talking about.

 

[Smykowski]

I'm willing to follow the methods here but not blindly nor immediately.

Part of the issue is that everything we teach is so contrary to the "mainstream" that newcomers to the site have a hard time with it at first, so yes, there is some level of "Trust us and do what we say." This may sound at first to be very similar to the pool store method, but we very quickly diverge from that track.

During the early stages of helping a new comer, every step of "Do this, this, and this" is accompanied by an explanation, plus a reference in pool school so that the newcomer can learn as well. All of the information is here to be absorbed, but most newcomers just want their pool fixed NOW, and don't take the time to research and learn, so by default the beginning part of the learning process has to be a "Do what I tell you." We hope to imply that you will learn along the way. As time passes, and knowledge is imparted, that newcomer no longer needs to ask the questions. They either know already from the experience they've gained, or they can figure it out by reading Pool School again or searching the forum.

At it's heart, this forum is not about maintaining other people's pools. It's about the philosophy of understanding pools and pool chemistry so you can take care of it yourself. Without sounding too tacky, this community is about pool empowerment.

 

[terryc]

Nice post. :lol: Here's still a point of contention that requires clarification.....

There are a lot that blindly follow and apparently get a little upset when someone questions the methods....

That's simply incorrect. Folks here are anything but blind and have taken the trouble to learn and understand how to manage their pools with remarkable success....nobody's blind.....quite the opposite.

Challenging what we know to be bullet proof science and remarkably consistent outcomes with faulty logic and misconceptions is what causes the somewhat emotional challenges you are getting.

We've hashed this stuff out over and over for 10+ years....we know what we are talking about.

Sorry, my argumentative side has to always throw one little barb out to keep things going. I always treat online forums like I'm beat friends with the people in them so just start with some good natured ribbing. Once people realize it comes from a good place they are usually ok with it.

My son has asthma so although I am cheap, I'm willing to spend a little bit extra to keep the chlorine usage down by using alternatives like borates and potassium peroxymonosulfate to kill of the chloramines instead of using a high FC level.

 

[JasonLion]

so just start with some good natured ribbing

Comments like those are disrespectfully and a violation of the rules of the forum. Please refrain from further "good natured ribbing".

Attempts to operate at lower FC levels almost always have exactly the opposite effect from the one you desire. For example reparatory issues associated with chlorine pool are not caused by chlorine directly, but instead by sanitation byproducts. Lower chlorine level favor the production of the more dangerous byproducts, while higher levels both discourage their production and speed up their breakdown when they are produced.

 

[chem geek]

I don't want to have the FC that high on a regular basis so about a 1/3 less on the chart should work for me and I'll have to figure out a way to keep my CYA down.

So you think that likely there is no adverse affects to prolonged exposure to chlorine at the 7 or 8 ppm recommended for a CYA of 60-80 or would you advocate just keeping CYA at 30 or below where possible.

Again, you need to get out of your head the idea that a high FC level alone means anything about "the chlorine is high, the chlorine is high, run for the hills". The chemistry simply does not work that way. With CYA in the water, the active chlorine level is VERY low where the minimum FC vs. CYA in the chlorine/CYA chart has the same active chlorine (hypochlorous acid) level as 0.07 ppm FC with no CYA (and no, that is not a typo -- 0.07 ppm, that's less than one-tenth of a ppm). 3 ppm FC with 30 ppm CYA has the same active chlorine level as 6 ppm FC with 60 ppm CYA and the same as 9 ppm FC with 90 ppm CYA. So the magnitude of the FC by itself is truly irrelevant. The only thing it tells you is the chlorine capacity or that held in reserve bound to CYA and effectively inactive -- not an oxidizer, disinfectant, etc. of any significance (technically, oxidizes one particular chemical over 150 times more slowly than hypochlorous acid).

So you should set your CYA level to that which reduces chlorine loss from sunlight to a tolerable level, but not being so high as to make fighting an algae bloom horrible IF one were to occur because the FC/CYA ratio got too low for whatever reason. Then after determining your CYA level, you set your FC level based on the chlorine/CYA chart which is the minimum required to prevent green and black algae regardless of algae nutrient level.

What Dave, Jason and others are saying is that the chlorine/CYA chart has been set to prevent green and black algae growth in virtually all pools (failure rate is less than 1 in 5000 pools, though it's such a low failure rate that it's hard to know for sure -- this does not count other known factors such as poor circulation). That is what is taught on this forum. If as an advanced user who thoroughly understands the chlorine/CYA relationship and its implications you want to use some form of algaecide (including the weak one of 50 ppm borates) and experiment in your own pool with a lower FC/CYA ratio, that is up to you since it is your pool, but it does have other side effects because lowering the active chlorine level doesn't just lower the algae kill rate, but the bacterial and other pathogen kill rate and the rate of oxidation of bather waste and it will have some of the chloramines (monochloramine, dichloramine) build up to higher levels though nitrogen trichloride will be lower. The level we have in the chlorine/CYA chart for algae inhibition turns out to be a reasonable balance between the chloramines as well, though in practice this only shows up under heavier bather load.

Again, it's your pool and you can do what you want, but that is very different than general principles taught on the forum that try to be applicable to virtually all residential pools.

 

[terryc]

Attempts to operate at lower FC levels almost always have exactly the opposite effect from the one you desire. For example reparatory issues associated with chlorine pool are not caused by chlorine directly, but instead by sanitation byproducts. Lower chlorine level favor the production of the more dangerous byproducts, while higher levels both discourage their production and speed up their breakdown when they are produced.

I know and that is why I said I'm willing to spend a little more to use alternate methods for removing chloramines or contaminants that produce chloramines instead of just letting high FC levels do the job. Do you really think that Chlorine has no detrimental affect at high levels over long periods of time? It probably doesn't in an outdoor pool, but are we 100% sure.

I will stand by my statement that it seems that many follow and defend the recommendations blindly based on the results. I, however, do not think that the recommendations were produced blindly or without research and merit. So to be clear I think that the methods and recommendations here are valid and will produce a great looking pool and are based on solid science. I also don't think that everything else and all other methods are snake oil. I was just asking questions and/or stating how I thought things worked. I was wrong in most instances and right in others.

 

[terryc]

I don't want to have the FC that high on a regular basis so about a 1/3 less on the chart should work for me and I'll have to figure out a way to keep my CYA down.

So you think that likely there is no adverse affects to prolonged exposure to chlorine at the 7 or 8 ppm recommended for a CYA of 60-80 or would you advocate just keeping CYA at 30 or below where possible.

Again, you need to get out of your head the idea that a high FC level alone means anything about "the chlorine is high, the chlorine is high, run for the hills". The chemistry simply does not work that way. With CYA in the water, the active chlorine level is VERY low where the minimum FC vs. CYA in the chlorine/CYA chart has the same active chlorine (hypochlorous acid) level as 0.07 ppm FC with no CYA (and no, that is not a typo -- 0.07 ppm, that's less than one-tenth of a ppm). 3 ppm FC with 30 ppm CYA has the same active chlorine level as 6 ppm FC with 60 ppm CYA and the same as 9 ppm FC with 90 ppm CYA. So the magnitude of the FC by itself is truly irrelevant. The only thing it tells you is the chlorine capacity or that held in reserve bound to CYA and effectively inactive -- not an oxidizer, disinfectant, etc. of any significance (technically, oxidizes one particular chemical over 150 times more slowly than hypochlorous acid).

So you should set your CYA level to that which reduces chlorine loss from sunlight to a tolerable level, but not being so high as to make fighting an algae bloom horrible IF one were to occur because the FC/CYA ratio got too low for whatever reason. Then after determining your CYA level, you set your FC level based on the chlorine/CYA chart which is the minimum required to prevent green and black algae regardless of algae nutrient level.

What Dave, Jason and others are saying is that the chlorine/CYA chart has been set to prevent green and black algae growth in virtually all pools (failure rate is less than 1 in 5000 pools, though it's such a low failure rate that it's hard to know for sure -- this does not count other known factors such as poor circulation). That is what is taught on this forum. If as an advanced user who thoroughly understands the chlorine/CYA relationship and its implications you want to use some form of algaecide (including the weak one of 50 ppm borates) and experiment in your own pool with a lower FC/CYA ratio, that is up to you since it is your pool, but it does have other side effects because lowering the active chlorine level doesn't just lower the algae kill rate, but the bacterial and other pathogen kill rate and the rate of oxidation of bather waste and it will have some of the chloramines (monochloramine, dichloramine) build up to higher levels though nitrogen trichloride will be lower. The level we have in the chlorine/CYA chart for algae inhibition turns out to be a reasonable balance between the chloramines as well, though in practice this only shows up under heavier bather load.

Again, it's your pool and you can do what you want, but that is very different than general principles taught on the forum that try to be applicable to virtually all residential pools.

Awesome post, thanks. I'll try to keep my posts of questions about alternatives in here or in chem201. I understand how the binding of CYA to chlorine makes a large percentage of the FC ineffective. However, I'm not sold on the binding making the chlorine/CYA combination benign and non-harmful? Is that the case? I'm fairly new to all of this but I think someone posting what they are doing and the results could be beneficial to the group or others that are willing to take a little risk/$$ to lower chlorine usage and if several start to have the same kind of results as only managing to the FC/CYA percentage then we are on our way to a better method that is tried and tested over thousands and thousands of pools with almost no exceptions. It all starts with one.

 

[JasonLion]

Do you really think that Chlorine has no detrimental affect at high levels over long periods of time?

No of course not. Chlorine is known to not be totally safe. If you want to be totally safe you certainly should never get in a swimming pool. If you are going to swim, you need to compare the relative safety level of the various things you are proposing. Higher chlorine levels introduce risks roughly on the order of one in a billion cases, while lower chlorine levels tend to subject you (indirectly) to risks that are roughly at the one in ten thousand cases level. Unless you are aware of every one of those lower chlorine level risks, and have taken steps to mitigate them (assuming that is even possible) you won't have the desired outcome.

 

[terryc]

Do you really think that Chlorine has no detrimental affect at high levels over long periods of time?

No of course not. Chlorine is known to not be totally safe. If you want to be totally safe you certainly should never get in a swimming pool. If you are going to swim, you need to compare the relative safety level of the various things you are proposing. Higher chlorine levels introduce risks roughly on the order of one in a billion cases, while lower chlorine levels tend to subject you (indirectly) to risks that are roughly at the one in ten thousand cases level. Unless you are aware of every one of those lower chlorine level risks, and have taken steps to mitigate them (assuming that is even possible) you won't have the desired outcome.

I have been sold on the need for a test kit to get a more accurate level of CC which is what is the really bad stuff I think. I'm just waiting to see if I get banned before purchasing from tftestkits. I am doing things to mitigate the issues with lower chlorine levels such as borates and potassium peroxymonosulfate.

 

[JasonLion]

However, I'm not sold on the binding making the chlorine/CYA combination benign and non-harmful?

Are you therefore somehow sold on borates and potassium peroxymonosulfate being benign and non-harmful? And if so why?

Borate is known to be dangerous at high levels and as far as I can tell it has never been tested throughly enough to decide either way at the one in a billion risk level.

 

[terryc]

However, I'm not sold on the binding making the chlorine/CYA combination benign and non-harmful?

Are you therefore somehow sold on borates and potassium peroxymonosulfate being benign and non-harmful? And if so why?

Borate is known to be dangerous at high levels and as far as I can tell it has never been tested throughly enough to decide either way at the one in a billion risk level.

Good question. From what I've read about the peroxymonosulfate it is pretty benign. The borate may be a little more questionable. Like I said, I'll keep my posting to here or chem201. I'll assume that it is ok to explore/ask questions about alternate methods.

 

[chem geek]

I understand how the binding of CYA to chlorine makes a large percentage of the FC ineffective. However, I'm not sold on the binding making the chlorine/CYA combination benign and non-harmful? Is that the case?

Read the "Chlorine/CYA Relationship" section in the thread Certified Pool Operator (CPO) training -- What is not taught. You will see numerous links to peer-reviewed scientific studies in respected journals showing how chlorine bound to CYA is indeed far, far less reactive than unbound chlorine. It is not completely non-reactive, but is less reactive by at least a factor of 150 if not more. For disinfection and for reacting with negatively charged surfaces such as skin, it will be even less reactive than the factor of 150 because the dominant chemical species is negatively charged (HClCY^-). The chemistry is absolutely consistent with disinfection rates, inactivation rates, algae prevention (on the forum; the one scientific paper is an outlier), oxidation rates, and ORP. There is also virtually no skin absorption (based on CYA skin absorption studies). That thread is not new and if you spent time reading in the forum you would learn about these things -- as Dave (duraleigh) wrote, we've been at this for 6 years on this forum and with Ben Powell at The PoolForum and PoolSolutions for years before that where Ben started in 1997 (though had experience before that). This stuff isn't something we're pulling out of our, well, you know...

My wife also has personal experience of the difference CYA makes where she swam every year for 5 months in an indoor commercial swimming pool with 1-2 ppm FC and no CYA where her swimsuits would degrade over just one winter season (elasticity gets shot; occurs before fading since the suits are "chlorine resistant") and her skin gets flakier and hair frizzier. During the 7-month summer season she swam in our outdoor residential pool with 3-6 ppm FC and 40 ppm CYA and her swimsuits have lasted for around 7 or so years and the effects on her skin and hair are far less noticeable. The difference is so extreme that she now no longer swims in the commercial pool and instead we extend our season with expensive gas heating into the winter except for maybe 2 months.

From what I've read about the peroxymonosulfate it is pretty benign. The borate may be a little more questionable.

MPS itself is an oxidizer so will have some similar oxidative effects on swimsuits, skin and hair as chlorine and since it is not moderated in its strength by CYA some of its effects will be even stronger. It does not have a bleaching effect so its oxidative effects will be more like the elasticity changes, but quite frankly it's a selective oxidizer just like chlorine so will oxidize some things and not others and we know from spas using Nature² with MPS that you can't keep the water clear on that system by itself and need to use chlorine once a week or so. MPS does not produce chlorinated disinfection by-products and there is no evidence of it producing products that are mutagenic, genotoxic or carcinogenic of which I am aware. By itself, it is not a disinfectant, but at hot temperatures along with silver ions it can kill pathogens quickly so is approved by the EPA in the Nature²/MPS system for spas only.

As for borates, read Are Borates Safe to Use?

As for chlorine overall, the quantity of disinfection by-products in outdoor residential pools that are typically low bather-load is very small so trying to reduce active chlorine levels further doesn't make a whole lot of sense, especially if you don't have other methods of removing the organic precursors from the water. If you don't remove the dead skin cells and urea from sweat and urine, they will build up in the water at the lower active chlorine level such that their product of concentrations remains roughly the same so the amount of end by-products will be roughly similar. The main exception to this is with nitrogen trichloride in the chlorine oxidation of ammonia (and to some extent possibly with urea), but that level is already extraordinarily low.

The main concern with disinfection by-products is with high bather-load pools, especially indoors. This is where supplemental oxidation systems as well as precursor removal systems become useful, but that's a whole other discussion not really relevant to our outdoor residential pools that are very safe. However, since you seem to be the type that searches the Internet and finds information from all kinds of questionable sources, let me point you to a few responses we've already written to articles and papers regarding disinfection by-products to try and preempt such questions. Read the following posts or threads:

Asthma and Chlorinated Pools -- the Bernard papers
New Chlorine scare -- the triplet of Barcelona papers; read the later posts as well
Alternative to chlorine, peroxide? -- discussion of alternatives
continuation of the above -- includes epidemiological studies
BBB and chlorine health -- some additional and repeated info
Natural Swimming Pools -- one "alternative"
Campbell Environmental Systems -- one of many "alternative" examples that blatantly lie
EcoSmarte -- another example of an "alternative" that blatantly lies
converting my ecosmarte system to chlorine -- a table of relative kill times for chlorine (with CYA) vs. copper and silver ions
Interesting Study (Dissertation) on DBP's in indoor pools -- an analysis of an indoor pool study
Chloramines and FC/CYA -- my calculations using chlorine oxidation of ammonia models

By the way, in case it wasn't clear, I do not have a Ph.D. and though I majored in Physics and Chemistry (a field major -- they didn't allow a double-major since there are too many common math and other courses between these two), I later got an MBA and most of my work has been in computer software programming and management. I am not a chemist. So if you use titles or position alone as a measure of credibility, then you should discount everything that I write. That's one reason I try and refer to credible sources and have you, the reader, use your own abilities to ascertain the truth.

 

[UnderWaterVanya]

Let me jump in with pure and unabashed lack of science...

While I read the science and understand most of it, and I get that personal experience is about as useful as random internet claims I feel inclined to share...

My pool at shock levels with 55 CYA (last year) was repeatedly mistaken for a pool with no chlorine due to the complete lack if CC's etc. Additionally, my son has eczema which is related to asthma and it is better when he swims in the pool.

What's this mean to you? My advice is to try this method without extra chemicals first then decide how it fits. Also if you really want to hold down the levels invest in a SWG.

Sent via Tapatalk...

 

[terryc]

By the way, in case it wasn't clear, I do not have a Ph.D. and though I majored in Physics and Chemistry (a field major -- they didn't allow a double-major since there are too many common math and other courses between these two), I later got an MBA and most of my work has been in computer software programming and management. I am not a chemist. So if you use titles or position alone as a measure of credibility, then you should discount everything that I write. That's one reason I try and refer to credible sources and have you, the reader, use your own abilities to ascertain the truth.

I started college life as a chemical engineer and then switched to computer systems with a master degree in software engineering. Your post are great and very informative. I like to joke around a bit and I know it has been taken wrong but I really do feel like this site is a great resource. Plus, often times the non PhD is far more practical than his PhD counterpart.

 

[chem geek]

I didn't intend it to be hurtful so I'm glad you actually didn't take it that way (I should have left out the phrase "seem to be the type that"). I'm trying to get you to be more discerning in your education with regard to giving different weight to different sources of information. Otherwise, it's going to get very annoying to respond to links of all the garbage information that is out there and quite frankly I'll just give up at some point. After you linked to it, I have written to the Ph.D. author of the article that confused perborate with borax and I'll post an update with what she says, but there's no way I'm going to try and correct the hundreds of inaccurate websites out there. When the CDC refers to "some environmental groups", they are being quite generous since the better organizations don't claim borax is OK -- it's more of the fringe sites (of which there are very many) that get their science all mixed up and many make up pseudo-science to match their agendas.

I'm a realist and absolutely understand that chlorine produces disinfection by-products and that some of these are mutagenic/genotoxic and that in extreme situations of poorly managed indoor high bather-load pools probably result in increased cancer risks and certainly bad air quality that is unhealthy for chronic conditions. However, chemicals and health is all about the dose and the dose of such by-products in outdoor residential pools is very low and is still low (though not as low) in residential spas. There aren't any great alternatives because hypochlorous acid is such a fantastic disinfectant at very low doses. That's just the way the chemistry worked out and doesn't preclude some new method coming along that would work well. There are already methods that could probably fit the bill but tend to be impractical in expense such as using ozone in the bulk pool water requiring high-end ozonators and very fast turnovers (i.e. massive pumps and very large piping and large-scale diffusers), but even that hasn't yet achieved EPA approval to prove safety from ozone outgassing. And it's all about risk -- read the Natural Swimming Pools thread I linked to so you get an idea of the gastrointestinal risk rate, though that does not account for virus transmission from person-to-person.

On another forum on spas, I kept track of all the incidents of hot tub itch/rash/lung as well as one case of Legionnaire's Disease that nearly killed a spa user, and most were due to either too low a chlorine level (usually letting it get to zero by not dosing enough to handle bather load), an extended use of Dichlor so too high a CYA level (without proportionately raising the FC level), or to the use of alternative disinfectants. So the real health issues from not doing proper maintenance or the right kind of disinfectant tends to show up more in spas since the higher temperatures and high bather-load (small water volume) tends to lead to runaway bacterial growth and biofilms much more readily compared with residential pools where algae is the more common "problem".