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catfish
07-05-2012, 06:44 PM
I'm having a hard time finding information on using high saline as a permanent, maintenance-free solution. To avoid corrosion issues, I envision on making it aesthetically closer to an artificial pond, with a dark bottom and natural looking borders that make small amounts of detritus acceptable. Filtration would thus be unnecessary. As with the beach, there'd be a shower nearby to rinse off the salt residue. (As a Floridian, heating would be a unnecessary luxury.)

To me this seems like an all around winner for someone that wants something aesthetically pleasing and completely sanitary with no maintenance whatsoever other than some skimming. But with the rise of salt-assisted chlorine generation, it is darn near impossible to find any information on this... costs, unexpected side effects, salt-tolerant organisms...

Speedo
07-06-2012, 03:03 PM
I've heard that ocean salt water is around 30,000 ppm and most SWCGs require around 3000 ppm. The generator creates chlorine which is what sanitizes your pool. I don't know about ocean water, but I'm doubting it's possible to sanitize your pool using only salt (at any level).

Using a quality test kit and swcg, how is that not practically maintenance free? It's the lowest amount of maintenance possible.

catfish
07-06-2012, 03:52 PM
well, my point is it's pretty safe to swim in the ocean, no? High salinity kills almost all pathogens you have to worry about. There's red tide I guess, but I don't think that's very likely to show up in one's back yard (then again, maybe I'm wrong?) What harmful or unsightly organisms do you think I'd have to worry about with ocean level salinity?

My research has revealed that there is a "swimming pond" industry, but this appears geared towards fresh water solutions, with plants used to create a balanced ecosystem. Some people might consider this "safe enough", but at least down here in sunny FL we have a nasty little amoeba called Naegleria Folweri that, while it infects swimmers only very rarely, has a mortality rate of over 98%.

Salt kills that critter and just about any other free roaming water critter that can harm you. You don't even have to limit yourself to ocean salinity... you could go all the way to dead sea salinity (~30% salt) if desired... which will kill all microscopic life, period. My research has revealed that pretty much every nasty thing that will *spontaneously* grow in the water does not do well at all if you dump salt in it. There might be a couple halophilic algaes, but I've yet to find out if they are likely to spontaneously arise and if they are, whether I can kill it by simply increasing salinity by another couple percentage points.

>Using a quality test kit and swcg, how is that not practically maintenance free?

Because the swcg can break and I'll probably be lazy about testing. Also, I believe salt is probably safer and healthier than chlorine of any form. The human body was designed to handle salt... aggressive oxidizers, not so much. I plan on spending a lot of time in my pool and I have some respiratory issues, so I'm just hedging my bets.

PoolDoc
07-06-2012, 05:22 PM
I'm having a hard time finding information on using high saline as a permanent, maintenance-free solution.

Unfortunately, "permanent, maintenance-free solutions" to pool chemistry are right up their with perpetual motion machines, auto engines that get 200 MPG, 'green energy' solutions to US power needs that don't kill birds, don't consume real estate, don't cost much, and do run 24/7 even when the sun doesn't shine and the wind doesn't blow.

Consequently, the only "information" you could possibly find would be what's generated by dishonest sales and marketing types looking for a 'mark' to sucker.


well, my point is it's pretty safe to swim in the ocean, no? High salinity kills almost all pathogens you have to worry about. There's red tide I guess, but I don't think that's very likely to show up in one's back yard (then again, maybe I'm wrong?) What harmful or unsightly organisms do you think I'd have to worry about with ocean level salinity?

You're not wrong about the red tide, but you're pretty much wrong about everything else.

There've been quite a few articles in the news lately about sewage contaminated beaches, and the fact that the EPA apparently considers a beach acceptably safe if only 1 in 20 swimmers gets sick! So if that's your standard of safety, well, everything is OK, right?

Wrong.

What most people don't get, is that the stuff in pools that makes swimmers sick almost always CAME FROM OTHER SWIMMERS. Snot, pee, sweat, poop -- about 1 gram or a pencil eraser's worth from EACH swimmer -- tears, toe jam, etc. are ALL just packed full of bacterial goodness, or sometimes, viral fun and games. NONE of these little beasties are killed by salt water, and people DO get sick every day because they are swimming in somebody else's poop. They don't BREED in salt water, but then they don't breed in fresh water, either: they breed in people!

Fish poop is not too likely to make you sick, but people poop will do it quite handlily, and dog and cat poop can give you fun that will last for weeks, months or even years.

You may be thinking, "But, it's only MY family's poop, and THEY are clean!" Maybe. People can be carriers of all sorts of things without having symptoms. But even apart from that, you don't want your trusted family member's poop in your eye . . . and if you swim in a pool without chlorine, that's just what you'll get.



Salt kills that critter and just about any other free roaming water critter that can harm you. You don't even have to limit yourself to ocean salinity... you could go all the way to dead sea salinity (~30% salt) if desired... which will kill all microscopic life, period.

No, you're on to something. It's not a solution for everyone, but I think this is EXACTLY what you should do: add 10,000 pounds of salt to a 10,000 gallon pool. (Just not in California, where you'll need a hazardous discharge permit, to drain your pool!)


Because the swcg can break and I'll probably be lazy about testing. Also, I believe salt is probably safer and healthier than chlorine of any form. The human body was designed to handle salt... aggressive oxidizers, not so much. I plan on spending a lot of time in my pool and I have some respiratory issues, so I'm just hedging my bets.

+ has respiratory issues
+ is careless about testing
+ makes pool treatment decisions based on some severely sketchy research . . .

Hm-mh. My older son had severe chronic asthma, and my mom died of IPF, so I've some knowledge of 'respiratory health issues'. I think I'll say, "Good bye", while I still can.

I don't think we can really help you with your pool, so the best I can do for you is offer you my best wishes for your good luck!

catfish
07-06-2012, 09:06 PM
Not quite sure where this hostility is coming from, nor why the post was moved to a section I have clearly indicated does not apply. The very small amounts of salt necessary to generate chlorine has nothing to do with what I am attempting to research. I'm not trying to convert anyone else to the idea; I'm merely interesting in finding out more. If it's true that poor hygene prevents this from working on a larger scale, that's fine. Personally I don't have a problem with wiping my butt before I go for a swim.

So you are saying virus can survive for non-trivial lengths of time in water that is, say, double ocean salinity? Do you have any sources you could refer me to? For bacteria, my question is what will they consume to survive? Bacteria have to eat to stay alive just like anything else.

Do you think I'm trying to sell something? Think about it. I would think that pure salt solutions would be the *least* commercial thing one could possibly imagine. Salt doesn't have to be expensive if you put in some time and find an industrial/wholesale source of unrefined stuff. If it were really that expensive, "salt poachers" would be making millions off of the shores of utah's salt lake and the dead sea. Or hell, a tanker tractor-trailer costs what, maybe $150k? and how much seawater could one of those things haul? Now, how much to rent one for a day? That's the expensive, cumbersome route and it's still likely feasible for someone reasonably well off. And frankly I could not care less about whatever wacky laws calfornia has come up with.

Millions of people swim in Florida freshwater ponds every year, unaffected. If you feel like arguing volume effects, I have enough land and will soon have enough money to construct a pond of similar size to many of the local places. But I am trying to be considerably safer than them, *safer*, so what are you all in a huff over? Is this forum a front for a pool supply company or something? Look if you want chlorine that's fine, I've grown up with the stuff and I'm just sick of faded shirts and allergies and the everpresent chemistry set. But I'm sure chlroine easier and I'm sure the upfront costs are tremendously cheaper. And you'll probably kill more bugs with a high chlorine setup vs. an ocean level salinity setup. That's fine. Everything has tradeoffs. I'm willing to compromise, but I don't want to risk brain eating amoebas and other crap that fresh water brings. I enjoy exploring the road less traveled; I don't advocate everyone come and join me.

I'd say "this post doesn't belong here" but a comment like that is just inviting a delete I suppose. Oh well, if that happens I'll be quick with the whois lookups to find out what commerical enterprise is behind this forum, because nothing else would explain such an overreaction to what is a simple request for ideas, firsthand experiences and scientific sources.

catfish
07-06-2012, 09:23 PM
To clarify, my research wouldn't be so sketchy if it weren't utterly impossible to google. You just can't look for info on salt water pools without running into a tidal wave of debate on chlorine generation, a murkiness you've helpfully increased by moving my post here. I'm sorry I didn't add a disclaimer before every one of my sentences that I do not know many solid facts at this point, except that I'm pretty darn sure the issue is not as cut and dry (no pun intended) as you make it.

And I don't doubt that sewage contamination of seawater does occur; I just am curious about: saline levels required for pathogens to survive, ratio of initial level contimination (much lower for not wiping one's butt vs. mass discharge) to volume (a pool or pond is obviously much smaller than the ocean, but how far does sewage contamination spread before the pathogens die off? Certainly it does not spread throughout the entire ocean, so the volume of waste/volume of water situation is not clear cut.)

If you feel so very passionately about people swimming in untreated water, I suggest you get down here right away with your sandwichboard and bullhorn, because there are literally millions of people taking a much bigger risk things than what I am contemplating. And that's all it is right now; contemplating.

Watermom
07-06-2012, 10:33 PM
Thread locked by moderator until Ben decides if and when he chooses to reply.

PoolDoc
07-07-2012, 01:23 PM
Mods, I'm re-opening it and moving it to the China Shop, just for fun. Usually, when people say dumb stuff, they are still asking for help, so I have to bite my tongue, and not say what I'm really thinking. It's nice to be able to speak more openly.

Plus, this thread will get Googled, and will serve as a nice repository for comments on the more extreme misconceptions about salt in pool water.

I'm going to let Chem_Geek respond, if he wants to, before I do so again. He'll be much nicer, if perhaps recondite.

chem geek
07-07-2012, 04:32 PM
There are over 35,000 scientific peer-reviewed papers in respected journals regarding bacteria in the (salty) ocean. There's no way I'm going to list all of those here. In this paper (http://www.ncbi.nlm.nih.gov/pubmed/19823914?dopt=Abstract), they isolated 519 different strains of bacteria looking for those that might be antibacterial (which sounds crazy, given they are bacteria, but they mean where one strain of bacteria produces substances that inhibit/kill many other strains) and there is also this paper (http://www.ncbi.nlm.nih.gov/pubmed/16386284) regarding fecal bacteria in coastal wetlands. As for viruses, salts kills some, such as H1N1 as described in this paper (http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0028043), but not others as described in this paper (http://www.sciencedirect.com/science/article/pii/S0044848611009203), this paper (http://www.sciencedirect.com/science/article/pii/S0168706907170051), this paper (http://www.sciencedirect.com/science/article/pii/0043135475901815), this book (http://books.google.com/books/about/Concentration_of_Adenoviruses_and_Norovi.html?id=a p1t4QYARmoC) and many others. Perhaps you should buy the book Oceans and Health:: Pathogens in the Marine Environment (http://www.amazon.com/Oceans-Health-Pathogens-Marine-Environment/dp/1441920129).

Look at the CDC Surveillance Summaries for Waterborne Disease and Outbreaks (http://www.cdc.gov/healthywater/statistics/wbdoss/surveillance.html) which show outbreaks in recreational water including marine water and in fact in all untreated water where the outbreaks have varied sources whereas treated sources (i.e. chlorinated water) had mostly the protozoan oocyst Cryptosporidium parvum which is why the CDC Model Aquatic Health Code (MAHC) is looking at requiring UV or ozone in new/modified commercial/public pools.

A critical point that is being missed, however, is the volume of water. Oceans have a very large volume so when you swim in them the fecal bacteria that you shed get diluted greatly. The same is true in large lakes and in flowing rivers. Even so, people still get sick in such water venues. However, swimming pools are very different in that they are much lower volume and are mostly static. The fecal bacteria you shed, as well as the viruses and protozoan oocysts (if you are sick) all go into a much smaller volume of water where the bacteria can reproduce at will and the other pathogens survive until they find another host (i.e. swimmer). Salty water is not sufficient to kill or inactivate such pathogens and certainly not to do so quickly enough to prevent person-to-person transmission of disease. Remember that human body fluids already are at around 9000 ppm salt and that many of early microorganisms came from the sea so have mechanisms for dealing with salt.

And then there's the impracticality of having very high salt levels in swimming pools with the attendant metal corrosion issues, stinging eyes (do you open your eyes underwater in the ocean?) and killing of plant life and contamination of waste water treatment plants for inland locations whenever you backwash or otherwise replace the water.

I believe your idea needs a little more thought.

PoolDoc
07-07-2012, 05:21 PM
Thanks, CG.

BigTallGuy
07-10-2012, 12:49 PM
Catfish, I understand your request for information, however, I want you to take a step back and consider the following.

I honestly believe Ben, the Administrator, is trying to help you with your research by sharing information regarding the safety and sanitation of your pool project. If you really want to look at the big picture, it is not only about “wiping my butt before I go for a swim” or making sure everyone visits the bathroom before diving in. It is about pool sanitation with regards to not only human wastes, but animal wastes (dogs, cats, birds flying overhead etc.) and insects too. I clean flies, bees, grasshoppers, etc. out of my skimmer constantly, and who knows what they bring to the pool. I believe Chem-Geeek has provided enough information to prove that Salt alone, in most cases, is not a sanitizer in swimming pools.

This Forum is comprised of a lot of good people that get nothing more than the satisfaction of helping people across the US and Canada with their swimming pool problems. We get a full array of people seeking help and information, everything from rich people with huge swimming pools to single Moms with small above ground pools. Our charter is to provide sound advice, to the best of our ability, for the safety and affordability to all. We would be remiss if we didn’t advise you (or anyone else) of what we have learned or what has been proven.

Unfortunately, a website like this also attracts a boat load of spammers as well as “Know-it-alls” that are mostly mouth and very little ear. If you choose to continue to visit this Forum, you will learn that there is no corporate sponsor or commercial enterprise subsidizing this Forum. In reality, we primarily promote the BBB method which fundamentally promotes pool care with grocery store items that basically undermines the profits of all of the Big Pool Chemical Companies as well as a slew of Pool Supply Stores. Pool cleanliness and sanitation is paramount with the BBB method, simply put, if it didn’t work, what good is it? The BBB method has withstood the test of time because it works.

We have seen the gamut of “Trouble Free” and “All Natural” claims, and virtually all fall short. There is no Known “Free Lunch” when it comes to swimming pools and their care, including performing simple tests. If there was a secret or magic pill with regards to swimming pool setups, I’m sure the people on this Forum would know about it, and in all probability you’d read about it first, right here.

In the end, it is your project and idea. Your safety and health, and that of your family, friends, and guests, that would potentially swim in your pool is in your hands.

catfish
07-11-2012, 04:40 AM
I think the disconnect here is the interpretation of "there is no free lunch" as "you must pay $0.99 for a McDonald's double cheeseburger; everything else is crap." The inertia of the status quo should not be elevated to a dogmatic religion. Everything in life is a tradeoff.

So let me begin by saying I was not aware of virus resistance to high salinity, and I think UV light shows great promise, being ultimately (though maybe not in the currently available implementations) low maintenance, low cost, low side effect and highly effective. That said...

I believe Chem-Geeek has provided enough information to prove that Salt alone, in most cases, is not a sanitizer in swimming pools.

Nonsense. I was going to invent a hypothetical pathogen that was resistant to chlorine just to make my point about life being mostly about tradeoffs, not right ways vs. wrong ways. But chem geek has helpfully provided me with a real example: Cryptosporidium parvum.

He made some good proof-of-concept points. Extrapolating that out to concrete, unshakable conclusions that cause administrators of large forums to ban or obscure discussion of anything not toeing the status quo is annoying at best. Health statistics are rarely as cut and dry as you think. Example: Everyone (especially politicians) still won't shut up about how much money smokers are costing us in healthcare. *Wrong*. They actually save society quite a bit of money by dying an average 7 years earlier, even taking into account the cost of their lung/cancer treatments. And that's without even considering the extra sin taxes they pay.

A better example: condoms. Fantastic efficacy on paper, mediocre performance in real life because people make mistakes or just don't care to use them right. When deciding how best to fight AIDS in Africa, which statistic is more important? The one that reflects actual reality, of course. Similarly, any comparison of chlorine to salt water should in the context of infectious disease should use real world figures, taking into account everyone who has a screwed up pool chemistry and doesn't know/care.

"Look at the CDC Surveillance Summaries for Waterborne Disease and Outbreaks..."

I skimmed the reports and, though it's entirely possible I am missing something important (sadly I do have a life), it appears they are relying on voluntary self-reporting of *mass* outbreaks from public health agencies. In other words, they are useless. Even if small-scale (personal, not public) chlorinated pools were ten times more infectious than the ocean on a per-person per-hour basis, you still wouldn't see any mention of it on those reports. There *might* be an implicit approval of public pool chlorination in there, but there is nothing I could see applicable to a smaller saltwater body mostly sheltered (see below) from animals and pollution/sewage discharges, and used by a small group of people.

"do you open your eyes underwater in the ocean?

Nope. Nor in pools. Both make my eyes sting.

"metal corrosion issues"

Then don't put metal stuff in the pool? Certainly, any fool that dumps huge quantities of salt in their existing, conventional pool and flips on the pump gets what he deserves.

"and killing of plant life and contamination of waste water treatment plants for inland locations"

Most pools aren't very far inland for the simple reason that most of the population lives pretty close to the ocean. (Go find nighttime pictures of the earth if you don't believe me.) Salt is already legal to buy, and in large quantities. I'm aware that, in the course of human events, the government may need to enact laws to keep stupid people from doing very stupid things, but this is neither here nor there. If you must harp on it, just keep in mind that the stupidity cuts both ways--most people cannot seem to keep their pool chemicals anywhere near where they should be.

"A critical point that is being missed, however, is the volume of water.

I already covered that. And it's not volume, it's contaminant/volume.

The problem with citing marine statistics is that a saltwater pool or pond would not be exposed to the same marine organisms. Comparing sewage contamination is even trickier.

As I said, I'm halfway-seriously thinking about something much bigger, but let's assume not. I don't know what you yankees do, but a regular sized inground pool is frequently/usually enclosed by screen down here... mosquitoes and pine needles are way too annoying. And a good screen will cut out almost all of the animal contamination issues, leaving behind perhaps a few small bugs. So does that leaves mainly person-to-person transmission, or are smallish insects and arachnids enough to introduce harmful pathogens? Person to person transmission can indeed be significant, but it entirely depends on what you, your family, and your guests' habits are.

My conjecture, assuming everyone wipes their bottoms: if you forget to wash your hands before eating (or before touching your eyes, mouth or nose) as little as 5% of the time, and your guests/family do the same, your fecal/oral transmission rates aren't going to be significantly affected by a little saltwater dip. And how quickly do all of those fecal-oral organisms die in chlorinated water anyway? Right away? I bet not... the real statistics aren't about killing vs. not killing, it's time-to-kill xx%, which probably isn't hugely relevant if you're swimming a few feet from the infected person.

Yes, I play fast and loose with conjecture for the simple reason that millions of people already take much worse risks, and it definitely unclear whether the current solution is ideal. I appreciate the factual responses, but the attitude and conclusions are sickening. You know, we are still stuck using gasoline engines that run on a very limited set of fuels, have crap mileage and crap fuel density, and simply wear out in under 200k miles because "duuuur, diesel is expensive!" Which, after a little bit of research and back of the envelope calculations, is clearly the opposite of true. Same attitude here, except the figures have yet to be shown, but that clearly doesn't stop the resident armchair biologists.

PoolDoc
07-11-2012, 10:09 AM
Catfish, I have to thank you.

I've been wanting -- for purposes that have nothing at all to do with the PoolForum -- to have a great, real-world example of contemporary post-modern reasoning: ie, 'there is nothing that's completely true, and I'm absolutely sure of that!'.

My older son had collected several examples from some of his professors several years back, but that was second hand. Yours is first hand, 'in your own words' so to speak and not enveloped in an academic context. I especially liked the way that you criticized some of the data sources for incompleteness, or for failing to screen data-selection errors (with some validity) and then turned around and noted (with exceptional validity) that
Yes, I play fast and loose with conjecture . . .

Who could argue with you, on that last point?

You are articulate, bright, and irrational -- a truly potent mix, and one that has become increasingly common as non-scientific higher education has abandoned rationality, except as a garnish or as a ploy in debate.

As for specific rebuttal of some of your claims, that will be hard to do coherently, since your claims and ideas are so scattered and directionless, but again, for the sake of the lurkers and Google, we'll try to take it up later when things are less busy.

I assume there's no functional urgency: it appears that don't have a pool problem, or even a pool, at present.

Gratefully yours,

PoolDoc

catfish
07-11-2012, 02:13 PM
Saying that the world is full of tradeoffs and saying that there is nothing completely true are two very different things. For instance, I never said and in fact disagree with the latter.

I will never forgive the postmodernists and naturalistic junkies, because they've basically sabotaged the ability to have a discussion about the relevance of empirical evidence, let alone discussing reasonable courses of action in the absence of it (hint: a diversity of approaches will actually provide you with the missing data.) It's funny, though, I bet if I mentioned the data linking chlorination to bladder cancer you would be quick to dispute it, perhaps even using analogies similar to the ones I resorted to. And of course, with the quote you use to mock my approach you conveniently discard the justification with ellipses.

So would I be irrational to swim in the local pond? Are all of the kids and parents irrational for doing so? How do you think we should best address such irrationality?

catfish
07-11-2012, 06:32 PM
Also, ftw, I have a degree in actuarial science and am well on my way to passing my second exam.

[ random fluff deleted - PoolDoc ]

And maybe all of that probably falls outside the expected scope of a forum like this, but...

well, it shouldn't.

PoolDoc
07-11-2012, 06:46 PM
And maybe all of that probably falls outside the expected scope of a forum like this, but...

well, it shouldn't.

My forum; my choice. Discussion of gastritis and the etiology of duodenal ulcers is not really germane here. If you want to start a swimming pool forum, where such things are considered OT, be my guest!

chem geek
07-11-2012, 09:27 PM
catfish,

I have to admit that I am totally lost with your reasoning. Yes, I understand tradeoffs, but when you initially said that high salt levels should kill off pathogens and then I provided information that showed that many pathogens including fecal bacteria can survive (and some thrive) in salt water, you seem to ignore that. Chlorine kills most pathogens very quickly and the most notable exception (mostly in commercial/public pools) is Cryptosporidium parvum. However, I completely am missing your logic of how that one pathogen justifies throwing out chlorine and replacing it with salt water. Crypto is planned to get handled, albeit slowly, via UV or ozone via the circulation system for future commercial/public pools in the U.S. Also, Crypto is usually not an issue in residential pools because it is only introduced into water from a sick individual (usually with diarrhea).

UV or ozone only kill pathogens that get circulated. They do absolutely nothing to pathogens on pool surfaces (bacteria tend to grow best on surfaces and form biofilms that are harder to kill so need to be killed quickly before that happens) and they also do not kill quickly since turnover times are generally measured in hours and it takes 5 turnovers to reach 99.3% of the water under ideal mixing conditions (only 63% of the water goes through the system for each turnover). You have to have a bulk water disinfectant of some sort to prevent both uncontrolled bacterial growth and to prevent person-to-person transmission of disease. Salt water alone doesn't allow for that. If it did, there would be no microscopic life in the ocean and I've already linked to human pathogens that survive in salt water.

As for the surveillance reports I referred to, they were by necessity for commercial/public pools and only for outbreaks since that is all that gets reported. But at least that's some sort of data compared to what you are providing (i.e. nothing at all). Residential pools tend to be safer due to the lower bather-loads and not having sick strangers visit the pool on a regular basis. However, there aren't good statistics about that safety since as you point out people who get sick from their pools will just, at most, go to their doctor and it won't likely get reported to any central government agency (and the doctor probably wouldn't associate the illness with swimming anyway). However, I CAN tell you from the experience of hot tub users that I tracked on poolspaforum.com that there were hot tub itch/rash incidents and one hot tub lung incident and one Legionnaire's Disease that nearly killed the person. I talked to these latter two people and to some of the others and believe me it's heartbreaking. Though most incidents were due to "too low or no chlorine" being used, some were from using "alternative" sanitizers.

Since the science shows that pathogens can live and grow in saltwater and since swimmers in pools are constantly shedding such bacteria (and viruses and sometimes protozoan oocysts) into a relatively smaller volume of water (compared to oceans, lakes and flowing streams), is your point that since there aren't consolidated reports of ill health from residential pools that we should not bother sanitizing them (since just using saltwater wouldn't be much better than fresh water)?

As for kill times, these are measured and well-known. One table of such times for some organisms is in this post (http://www.troublefreepool.com/converting-my-ecosmarte-system-to-chlorine-t24194.html#p205939) where I reference numerous peer reviewed scientific papers in respected journals (though apparently that doesn't carry much weight as far as you are concerned). The kill times for chlorine are VERY fast and this is at a level equivalent to 0.1 ppm Free Chlorine (FC) with no Cyanuric Acid (CYA) so roughly an FC that is 10% of the CYA level. Even at that low chlorine level, fecal bacteria are killed with a 3-log (99.9%) reduction in under 1 minute. Half are killed every 6 seconds. Now in practice, some fecal matter is released in clumped form so it takes somewhat longer. Nevertheless, chlorine is used precisely because it kills faster that almost anything else that is reasonably safe for human exposure. And the greater risk, when it comes to bacteria, is that of uncontrolled growth since larger bacterial concentrations can overwhelm the body's immune system. Also, bacterial safety is also measured in real pools as part of having to pass EPA DIS/TSS-12 (http://www.epa.gov/oppad001/dis_tss_docs/dis-12.htm).

There have been places, such as Australia, that tried using copper/silver since the combination (as you can see from the table) does kill though more slowly. Nevertheless, it is fast enough to prevent uncontrolled bacterial growth. What they found was that this wasn't good enough. It didn't prevent person-to-person transmission of disease and wasn't good at inactivating viruses so they pretty much ban its use in commercial/public pools and give strict warnings to those who want to use this in residential pools. Canada does the same thing.

Now if your argument is about relative risk, you can do whatever you want in your own personal residential pool, but there's no way that commercial/public pools are going to go to salt because all the evidence shows that it is not sanitary. If they go with some kind of alternative, it's not going to be salt, but more likely some other chemical combination like a quarternary ammonium compound along with potassium monopersulfate and with either UV or ozone in the circulation system, but only if they lower their standards for slower kill times.

As for the links of chlorine to bladder and other cancers, and since you have a degree in actuarial science, you should appreciate reading the Environmental Health Criteria 216 "Disinfectants and Disinfectant By-Products" (http://whqlibdoc.who.int/ehc/WHO_EHC_216.pdf) document. The bottom line with the epidemiology studies (including the ones on bladder cancer) is that they varies so some studies showed possible correlations while others did not. Furthermore, in most cases the odds ratios were < 2 and often < 1.5 with wide variations (standard deviation) due to fairly small sample sizes. All of this often means that there are confounding variables not being taken into account.

For example, if someone finds a higher cancer rate for those drinking chlorinated municipal water compared to unchlorinated well water, the correlation may be due to municipal water servicing cities and most well water being in the country where people may do more physical activity. So the real correlation may be with exercise and not with chlorine. It's this kind of effect that makes epidemiological studies dicey unless their odds ratios are high with large sample sizes and having multiple studies looking at a variety of variables (e.g. studies about smoking and lung cancer and other effects).

catfish
07-12-2012, 11:48 AM
My forum; my choice. Discussion of gastritis and the etiology of duodenal ulcers is not really germane here. If you want to start a swimming pool forum, where such things are considered OT, be my guest!

I'm not the one who brought up postmodernism.

catfish
07-12-2012, 12:28 PM
I've already admitted that I didn't previously consider human to human transmission to be the primary focus of pool sanitation, in particular the survivability and transmissability of fecal-oral viruses surprised me. Unlike many a pseudorationalist, I readily admit my previous lack of knowledge / foresight. From the data you provided, it does indeed sound like a rather bad idea to use ocean level salinty in a public pool. (Though I was never thinking about public pools to begin with.) This does not justify the torpedoing of the entire concept, any more than the bladder cancer research means we should abandon all discussion and approval of chlorine. Anyone can quote statistics; the real challenge is in connecting the positive to the normative. Well no, I'd say the real challege is to intelligently interpret all data involved, and not just the ones you agree or disagree with. (Which was the only reason I brought up bladder cancer.)

So, there is still the unaddressed question of hypersaline concentrations (the extra buoyancy would be pretty fun too), and the completely different scenario that home pools present (half a dozen mostly related people who are already touching the same doorhandles vs. thousands of unrelated visitors every day.)

Thesis statement: Salt, along with some other metals, (bismuth ftw if only we could find some large deposits) has a number of extremely attractive qualities: relative lack of adverse human health effects, low cost (don't quote me tiny, overpriced bags of purified retail stuff), and the permanance / lack of maintanence because yes, people are lazy and stupid and real world risk analysis does not simply ignore operator error. It is foolish to ignore these qualities and write off the concept because:

1. OMG SALTWATER SHOULDN'T BE DUMPED ON THE GROUND (I think well publicized incidents of stupid people poisoning their own topsoil and wellwater will help drive this point home. Fortunately, there are plants like Salicornia to help with the cleanup.)
2. OMG SALT CAUSES RUST (meh, steel is overrated and overused anyway. composites ftw)
3. OMG SOME STUFF CAN SURVIVE IN OCEAN LEVEL SALINITY (see above)

catfish
07-12-2012, 02:56 PM
Not wanting to spam, but I realize that nuanced reason can be tricky new territory for a data-spammer, so here is a more simplified version of my argument you have failed to rebut or even intelligently discuss:

1. A massive number of sources imply that dead sea level salinity all pathogenic organisms of concern (not considering massive discharges of sewage) on par with chlorine. I may be utterly wrong here; mainstream media sources can be easily wrong and I am not very familiar with the means by which saline deactivates some things.

2. Dead sea level salinity is affordable (if not the most affordable) for someone spending 5 figures on a pool.

3. Sodium chloride will be as affective as the magnesium salts the Dead Sea is dominated by.

There, all that distractingly eloquent language pruned. Happy?

PoolDoc
07-12-2012, 05:17 PM
1. A massive number of sources imply that dead sea level salinity all pathogenic organisms of concern . . . . mainstream media sources can be easily wrong

Without exception, I've found MSM articles, when covering topics about which I have independent technical knowledge, to be accurate only so long as they quote an accurate source, and further that MSM journalists generally have no ability to distinguish reliable sources from those that are merely politically correct. If they cite a source, then YOU need to find the source and cite IT, not the MSM article. That's what we do. That's what we expect of you, if you want us to bother with your argument.

And, if you want us to believe you that there are a "massive number" of sources . . . you need to list, if not a massive number, at least several dozen sources. Otherwise, we'll just conclude that you're spraying more fluff.



2. Dead sea level salinity is affordable (if not the most affordable) for someone spending 5 figures on a pool.

According to various sources*, the Dead Sea salt levels are around 300 ppt or 300,000 ppm. For a 13,000 gallon 24' round pool, that translates into 32,000 lbs of salt or 821 40# bags of salt. Assuming a hefty discount from the going rate ($6.50/bag) down to $4 per bat, that's still about $3,200 for salt. Considering that that's more than the pool would cost, I think we can dismiss your claim that "dead sea level salinity is affordable" as yet another case of thinking that's long on fancy and short on facts.

[* http://www.britannica.com/EBchecked/topic/154254/Dead-Sea ]



3. Sodium chloride will be as affective as the magnesium salts the Dead Sea is dominated by.

Given the general unreliability of your claims so far, I think we can safely ignore this one, at least till you cite sources.



There, all that distractingly eloquent language pruned. Happy?

Much happier; if you are going to say dumb things, saying them succinctly makes it much easier to recognize them for what they are. (And, of course, that's why politicians aren't brief!)

BigTallGuy
07-12-2012, 07:54 PM
Catfish,

I have never personally swum in the Dead Sea, nor in the Great Salt Lake in Utah. However, I have spoken to people that have. The resounding complaint from those people is that just about any tiny cut will sting and burn. The men I spoke with tell me that even shaving facial hair (assuming no cuts or nicks) with a standard blade type razor prior to swimming in the Dead Sea is irritating and uncomfortable to the face once you get in the water.

You already have stated that you do not open your eyes under water while in the ocean, as it stings your eyes. My question to you is this, why would you ever want to build a pool that would do the same thing only worse?

If you visit this website, you will learn that plants, animals and microbes live and survive in the Great Salt Lake, which is reported to be 3.5 – 8 times saltier than the ocean.

http://learn.genetics.utah.edu/content/gsl/physical_char/

Having had a traditional pool that irritated my children and grandchildren’s eyes, as well as my own, and my own grandchildren tell me that they don’t want to swim in my pool anymore because it burns their eyes, I felt pretty ridiculous. I realize that this is just a dream for you at this point, but my experience says you’re going to be pretty lonely in your pool.

But, in the spirit of education and sharing knowledge, here is a bit of information you may find useful.

1 tablespoon of Salt in a gallon of water is approximately 3600 PPM.

9-10 tablespoons in that same gallon of water will get you somewhere close the salinity level of the Ocean (35,000 PPM).

85 tablespoons will get you to the approximately the salinity level of the Dead Sea (300,000 PPM).

Perhaps you might want to mix up a small sample to test your theory before taking the big plunge and filling a pool.

AnnaK
07-12-2012, 09:10 PM
Ugh! Whoever would want to swim in such a concentrated salt solution? That would suck the water out of your skin in no time. I used to live near the Great Salt Lake. Nobody swims in it because it's scummy from algae which do very much survive and love highly salty water. I'm having a great time picturing 32,000 pounds of water in a 13,000 gallon round pool, imagining the salt sliding out of the dump truck, making a tall mound of salt in the middle. Catfish on top of it with a big rake pushing the salt into the water which, of course, is overflowing the sides. What stays in is getting very cold due to the exothermic reaction. Catfish is now up to his ankles in a supersaturated, very cold salt solution and we see the flesh dissolving off his feet . . . okay, I'll stop.

BTG has a good idea: try it in your bathtub, first. Sit in it for an hour or so, see what it does to your bottom. Ouch!

PoolDoc
07-12-2012, 11:33 PM
BTG has a good idea: try it in your bathtub, first. Sit in it for an hour or so, see what it does to your bottom.

To say nothing of other parts -- it might put an end to all thoughts of 'kittenfish'. ;)

Still, it would give him a chance to actually put some facts in his fantasy, and be a REAL investigator and pioneer. Maybe even, the last of his breed. :D :D

AnnaK
07-13-2012, 07:57 AM
LOL!

You know, this thread started out fairly interesting on kind of a "what if" level, but a 10 second search on Google produces an immediate Aha! response. The Salton Sea, the Great Salt Lake, the Aral Sea, the Dead Sea, California's Pink Lakes – none are used for recreational purposes. The caption to one of the photos of the Pink Lakes says "The red coloration is caused by astronomical numbers of microscopic, unicellular organisms living in the water and salt crust. How they survive the blistering summer heat and concentrated brine is truly remarkable."

I'm sticking with chlorine.

BigTallGuy
07-13-2012, 09:51 AM
I said it once and I'll say it again. There is no "FREE LUNCH" when it comes to swimming pool sanitation. You're gonna pay the price somewhere, somehow, but burning my skin is not a price I want to pay.

chem geek
07-13-2012, 10:32 PM
It doesn't help to move the goalposts around, so to speak. We started out talking about ocean salinity levels, but yes if we are talking about extraordinary salt saturation levels nearly 10 times higher then sure that may kill pathogens, but as was pointed out by others above is impractical for many reasons.

If we want to have a rational discussion about chlorine alternatives, we can have that, but why waste time going down dead ends? There are already quite a lot of alternatives we can discuss unless we're just having a brainstorming session online.

I didn't mean to discount the very real risks of chlorinated disinfection by-products. High bather-load indoor pools that aren't exceptionally well managed can be pretty darn awful in short-term effects (largely from nitrogen trichloride) and may be at least somewhat harmful for long-term effects (from brominated THMs and other chemicals, mostly regarding cancer). However, when I look at this data, I can see that reducing the active chlorine level to the lowest amount that still gives reasonable disinfection rates while simultaneously providing methods for removing organic precursors (i.e. bather waste) to oxidize them before chlorine does seems the easiest path to take, at least initially. I believe small amounts of CYA (20 ppm for indoor pools, for example) can be used for this purpose to have, say, the equivalent of 0.2 ppm FC with no CYA.

As for true alternatives, we need something for bulk-water disinfection and right now it looks like the quarternary ammonium compounds might be a reasonable candidate (I already discussed the problems with copper/silver, though for just preventing uncontrolled bacterial growth they are OK if one can deal with their levels and pH to avoid staining issues). UV or ozone can still be used to handle Crypto. That still leaves general oxidation of bather waste for which there are a lot of alternatives (ozone doesn't oxidize urea well, especially if it's not chlorinated, while UV only affects some chemicals). In addition to some selective oxidizers, such as MPS, the use of boron-doped diamond electrodes to produce hydroxyl radicals may be a good approach and might be one of the few things that can break down urea (other than chlorine, which does so slowly though possibly aided by the UV in sunlight that produces...hydroxyl radicals), though that remains to be seen.

And then there's the DIN 19643 system used in some countries in Europe that focuses on coagulation/filtration for removal of organic precursors, though they use low levels of chlorine in the 0.3 to 0.6 ppm FC range without ozone or 0.2 to 0.5 ppm FC with ozone (with no CYA, however, so still generally higher than I'm proposing).

Now for residential pools where person-to-person transmission of disease is a risk many would be willing to take since odds are they might catch something through other contact means (such as you described), then the focus is more on preventing uncontrolled bacterial growth and oxidation of bather waste. The same sorts of alternatives as described above could be used, but using a subset of them since the bather load is much lower. Just keep in mind that the risk is higher (though as a personal choice, may be acceptable) and usually the costs will be higher as well, at least up-front. I'm just very leery given my discussions with users of such systems when they failed, but realistically a properly designed system may not have the same problems as those that were used (or used improperly).

waterbear
07-16-2012, 10:26 AM
Also, ftw, I have a degree in actuarial science and am well on my way to passing my second exam.


In other words, a bean counter for the insurance industry! Explains a lot. A FAR cry from the actual hard science disciplines like chemistry, biology, and physics. More akin to an accountant that understands some statistics.



And maybe all of that probably falls outside the expected scope of a forum like this, but...

well, it shouldn't.
Probability is better left to describing an electron's position in its orbitals or perhaps at the roulette wheel and craps table in Vegas (or to the insurance industries, which is basically just another form of gambling, that are betting that they can get your money without having to pay you for a claim. If you are high risk they won't insure you!) then to the care of a swimming pools!

AnnaK
07-16-2012, 10:58 AM
Putting down someone's educational achievements, the job he holds, and the industry in which he works really isn't germane to this discussion.

waterbear
07-16-2012, 12:46 PM
I was merely pointing out that his expertise is in a different field and not one related to pool water sanitation such as chemistry, microbiology, medicine, etc. or even pool maintenance and operation for a variety of pool and not just his own.
His expertise would be in accounting and risk management (which is where the probability comes in).

I stand by everything I said and it was not a put down. It was a statement of fact. Just because one has higher education does not make them an 'expert' in areas not related to what they studied, not does it necessarily give them critical thinking skills (particularly nowadays).

BigDave
07-16-2012, 01:16 PM
I smiled at your post WB, but, AnnaK's right: "bean counter" is a perjorative. It also appears that you've swung a bear claw at catfish, the insurance indistry, and the statistical sciences.

On the other hand, I absolutely agree that catfish's assertion that a degree in actuarial science (+ one exam) validates these assertions is rubbish. I have observed that a high level of achievement in a particular field tends to engender a belief that the models and methods of one's expertise are universally applicable especially when these achievements are new. I have also observed that many if not most people make decisions based on loose conjecture, casual observation, and percieved consensus. They depend on a "sense" or "feel" of the world with no understaning of the facts or mechanisms surrounding thier decisions.

PoolDoc
07-16-2012, 02:19 PM
Anna, I sorta agree. But, I started it, for reasons I'll explain below. And, in any case, he's not logging in, anymore.

In part, Catfish earned it by playing the "I got more letters behind my name than you do, so I'm right!" card.

But nobody get's automatic cred here, even if they have a PhD in chemistry or biochemistry. I've talked to too many PhD's who live in the tiny world at the small end of their microscope, to have any idea of how even they things in which they are expert connect to anything in even their own personal worlds.

Chem_Geek denies it, but he currently is almost certainly the top expert in analytical pool chemistry in the world - and while he does have a degree in chemistry, he has no higher degrees in related fields. Over the years, I've talked to numerous PhD's either in the pool business, or in related fields, and while none of them were idiots (well, except the 2 who had PhDs in education, or in exercise science), MOST of them had no idea how, or whether, anything they knew had any practical relationship to an actual pool filled with actual water.

Anyhow, I've flagged this thread to come back and clean up, and convert to a web page.

There are numerous folk interested in the topic an "all natural salt-only" store. And, catfish is correct that there's very little good information about the topic. So, I felt it was worthwhile to create an online reference point, using Catfish as the straight guy. He actually played the part far better than I would have anticipated - when I posted the suggesting about Dead Sea salt levels, I was being facetious, but he took it straight up, and moved right into advocating extreme salt levels, which surprised the heck out of me.

Ironically, Catfish may have benefited somewhat from his actuarial studies in a way that WAS relevant to this thread. Most people have not really internalized the fundamental fact that 'man was born to die', and spend much of their life, money, and mental powers trying to hide from that fact. You can see this constantly here, in the way people constantly, persistently and resistantly, presume that there is some perfectly safe way to swim. As an actuary, Catfish seemed to have some awareness that this is NOT so, and that there is NO method of 'sanitation' that is without side effects, or that is fully effective against all pathogens.

It's just too bad for him that he couldn't extend that to a comparative risk/benefit analysis of salt alone vs chlorine. Of course, for the sake of the web page I want, he played the 'straight guy' role perfectly.

So, if anyone owes him an apology, it's me. I knowingly baited him, hoping he'd do what he did, and not only take -- all on his own -- an extreme 'natural salt' position, but also would elicit the data that Chem_Geek and others' provided. He started it, coming here with his "let me larn y'all about the REAL truth" attitude, but maybe I was wrong to treat him personally with the disrespect I did. I'll have to think about it.


But, I do think we're done here -- so I'm asking all support team members to back off, except to post straight data that you've found,
that's relevant to the topic of "all natural non-chlorine salt-sanitized" pools.

PoolDoc
07-16-2012, 04:07 PM
I have observed that a high level of achievement in a particular field tends to engender a belief that the models and methods of one's expertise are universally applicable especially when these achievements are new.

Hear, hear! (here ;) )

BTW, I hadn't seen any posts besides AnnaK's when I posted my long one above -- it was open for awhile. I should have copied it out, refreshed and checked for updates, and then copied back in . . . but I forgot to do so.

paulvzo
08-11-2012, 06:14 PM
Catfish (Hello? Hello?), have you ever been to the Dead Sea? The water is not "fun." It has a slimy feel to it. Perhaps this is due to salts other than sodium chloride. And wherever it evaporates, hard salts left behind.

Here is Sarasota, the beaches are sometimes closed to swimming for a few days after a mishap or overload at the sewage plants. Obvious reason.

PoolDoc
08-11-2012, 10:14 PM
Catfish hasn't been back since July 12th.

Spensar
09-07-2012, 12:57 PM
Gawd I love this forum.