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Richard A. Falk said:
I hate it when I type too fast and forget some key words. The above should have been qualified to say "copper at concentrations allowed in pools" since copper ions at much higher concentrations as well as copper surfaces do kill bacteria, though still somewhat slowly but fast enough for surface disinfection such as for use in hospitals and the like and it is this use of copper alloys that is approved for inhibiting bacterial growth on surfaces.
As shown here, Cl Free takes such EPA approval out-of-context and the actual press release with the wording they use is not to be found at the EPA (such as "Rigorous analysis by independent lab and hospital testing showed elimination of bacterial, fungal and viral pathogens within minutes."), but this same text is found (copied and pasted) in numerous other copper ionization websites including Carefree Clearwater, Coastal Pure, ToniQua. The actual EPA fact sheet notes that copper, when used in accordance with the label, “kills 99.9% of bacteria within two hours.” This is for copper alloy used in solid surfaces, not copper ions in water and most certainly not at the very low concentrations allowed in pool water (the maximum copper ion concentration allowed by the EPA in pools is the drinking water limit of 1.3 ppm (1.0 ppm as a secondary standard) and in practical terms it can't get that high anyway or else it will stain at usual pool pH.
Again, one can use these facts to show that these copper ionizer companes are being deceitful and one should ask their potential customers if they really want to buy from a company that has to lie or deceive in order to get their business.
This is a good point. Just as one example, all of the alternative products that use only copper ions for bulk-water sanitation using either copper ionizers or copper sulfate pentahydrate, such as Ecosmarte, Cl Free, Pristine Blue, Cleanwater Blue, Rain Forest Blue, Intec, etc., do not inhibit let alone kill fecal bacteria. This is because the normal copper ion blood serum levels in the human body are in the 0.7 to 1.5 ppm range which is at or above the level of copper ions found in pools. Fecal bacteria (including ones that are pathogenic when uncontrolled) that live in the human gut have explicit mechanisms for surviving and even thriving in such an environment. It's not just that copper kills too slowly, but that it doesn't kill AT ALL or inhibit (slow down growth) AT ALL when it comes to fecal bacteria. This is truth that should be told.
I give details about this including references to extensive scientific peer-reviewed articles in respected journals in this thread. I have also notified the EPA about some bactericide claims some of these products are making and this is currently under review. It should be very easy to compete against such systems countering their "chlorine is bad" by noting that your system operates at much lower active chlorine levels than found in the indoor pool studies (by at least a factor of 10 if you compare hypochlorous acid levels) and that copper-only systems are not safe from fecal bacteria. You could even offer bacteria test kits whose cost you fully refund for those that purchase your system (such tests should be made taking samples that scrape pool surfaces just in case they have ozonator or other systems that may kill some of the planktonic free-floating bacteria).
Copper-silver combo ionization systems are harder to combat since the combination does at least inhibit most bacterial growth, though does so too slowly for commercial/public pools since prevention of person-to-person transmission of disease is more important in that environment. Nevertheless, these systems are not very effective against viruses nor protozoa or their oocysts (chlorine isn't great against oocysts either, but is likely better than copper/silver ionization). However, if one is going the alternative route, this is at least one of the better alternatives if combined with a good oxidation system though it does have downsides since the necessary levels of copper and silver needed to be effective can cause staining and turn blond hair greenish unless the pH is kept lower.
Finally, Magnapool really should not be competing against the "alternative sanitizer" market anyway since that is a relatively small number of pool installations. The real market is that of saltwater chlorine generator pools since most new in-ground and many above-ground pools are sold with such systems. If your system truly reduces disinfection by-products, then you could replicate the same tests for chloramines and THMs as well as mutagenic studies on real Magnapool installations and compare that data to the studies that currently scare some people.
One should not fight deceit and untruths with the same, but rather expose them and fight them with truth.
As stated, you joined PGN to participate in open-minded dialogue. Generally most people have some bias, but after reading what is written, everyone can decide for themselves what is true, and what is best for them.
No doubt you believe that MagnaPool is the best systems for pools. It may be a good system. In general however, no system or product is perfect for all situations. There are usually pros and cons to everything, including costs, benefits, downside effects, time management, etc.
If your product is the best, then there is no need to embellish the benefits, or mislead about the shortcomings or differences between your system and the competition. As Richard stated, your advertising, sale pitch, and marketing of your product should be accurate and support the technical literature, and vice versa. Just because the competition may be making false claims does not justify doing the same. Inaccurate comments and claims can be defended. As you know, this forum has identified several false claims by various vendors. It is better (in the long run) sticking with truthful marketing.
I feel Richard is generating reasonable questions and comments regarding your system and the marketing of it. I doubt he is a competitor of yours, and is just trying to bring accurate information to light. I appreciate this forum providing me the opportunity and information to learn about a new product in our industry.
Richard A. Falk said:
I will not trade integrity for respect.
Particulate matter is filtered out via the pool sweep, skimmer basket, pool basket, skimmer socks (for pollen, etc. if one does not want to clean the filter as often) and the filter. There is no difference or benefit with MagnaPool for the larger items that get caught in traditional pool systems and any higher chlorine demand from these (especially pollen) is handled equally well by traditional pool systems. The question is the chlorine demand for the finer particles that (only) MagnaPool catches and that demand is simply not seen -- no major overnight chlorine demand with pump running and no sun on pool. Pools in sunnier areas have greater daily demand if kept at the same FC and CYA levels as pools in other areas. Even spas freshly filled with tap water have a daily chlorine demand even if unused that is largely a function of temperature that roughly matches the no sunlight demand in pools with no bather load (when adjusted for temperature). Removing finer particles for greater water clarity is fine, but this is not a significant source of chlorine demand seen in well-maintained pools.
Very, very few TFP members know pool chemistry. They can look at the Pool School as a reference and it is not technical. Many have saltwater chlorine generator systems so just check their pH once a week and adjust accordingly (as well as TA long-term). It is the manually dosed pools where those members add chlorine every day or two (or use pucks when on vacation) plus some acid every few weeks to months. Some use Hasa's The Liquidator or peristaltic pumps for feed systems. Others use pucks, but understand the consequences so have enough dilution or raise the FC level or use supplemental products as they choose. Some use borates which also makes the pools very forgiving. A few use phosphate removers. TFP is about education, but people can (obviously) do whatever they want. I'd like to educate them on MagnaPool and update threads already written on several forums, but I do not feel comfortable with parts of the system yet since little of what I wrote has been acknowledged so far, only dismissed.
The reason I harp on marketing text that you say is "nit picking pedantics" is because of posts like this one on another forum where someone who says they are a Doctor talks about the dangers of chlorine and that their MagnaPool is about minerals instead. Then that same person (after questioning) later clarifies in this post that indeed there is chlorine in their pool, but it is "natural chlorine" rather than "synthetic chemicals". The part of that post I am referring to is the following:
In actual fact, the chlorine in the water is identical regardless of chlorine source. The only differences from the different sources are in what else they add (like CYA or CH) and in their effects on pH. There is the valid argument of not having to handle chlorine vs. having it generated on-site, but if a person can be misled as this Doctor has (apparently) been, that means others can as well. Of course, this person may have been a shill for the company or a distributor. As I wrote before, it's shameful when some saltwater chlorine generator companies try and say they are just salt pools and don't talk about the chlorine, but two wrongs do not make this right.
There will be other questions that people will have such as the capacity of the filter to remove phosphates since some water districts put orthophosphate in the water supply so with evaporation and refill one can have 1000 ppb (1 ppm) or more phosphates every swim season. There are also pools that have used organic phosphate metal sequestrants that may have broken down to have several ppm of phosphate so people will need to know what will happen to the filter in that situation. How much will it handle? How can it be removed? We don't need to know exactly how things work, but it would be good to have at least rough ideas of where things are done since that leads to these sorts of very relevant questions.
Turbidity does not measure all organic precursors. It only measures those particles or chemicals that diffract (bend) or change the color of light. Turbidity does not change when there is more ammonia or chloramines or urea or chlorourea or other dissolved organic compounds in the water. Skin cells, probably, algae, probably, suntan lotion, probably, but not many dissolved organics and that includes trihalomethanes (THMs) themselves. (This paper describes how urea can be measured via turbidity but only by adding a reagent which combines with urea to form a precipitate). If you want to make any claims regarding THMs, then you had better do some actual tests comparing equivalent bather loads (and cumulative history) with a traditional saltwater chlorine vs. a MagnaPool and pay for the expensive THM tests (around $130 for each sample).
By the way, a large amount of THMs are produced from chlorine reacting directly with skin and that is something that will not, obviously, be removed so there is still a baseline THM level. The control of that can be done by reducing the active chlorine (hypochlorous acid) level via the FC/CYA ratio. If your system removes both orthophosphates and organic phosphates and possibly filters algal spores to the degree that algae is very much controlled, then a lower FC/CYA ratio can be used just for sanitation and that will lower the rate of THM production from skin. There are some very positive things that can be done if we only understood your system better.
Richard A. Falk said:
Just wanted to qualify the above which was calculated with a CYA of 0. With a CYA of 30 ppm and keeping TA at 100 ppm, an increase of 10 ppm FC (which is quite a bit higher than what is usually done) would raise the pH from 7.5 to 8.0 for such water coming out of the returns. The presence of CYA at lower levels essentially removes the pH buffering from the hypochlorous acid / hypochlorite ion system. Nevertheless, 8.0 still isn't close to high enough to keep magnesium hydroxide from dissolving and the bulk pool water won't normally be that high in pH anyway.
I'm now researching the phosphate removal claim which can't be from physical filtration so must be from adsorption or similar process unless some precipitating material is added (such as lanthanum chloride). The cellulose fiber manufacturers, such as Fiber Clear, also make such phosphate reduction claims so I'll find out the level of such reduction as well as the mechanism. In the case of glass filtration media, anionic (positive charge) surface properties could not only tend to capture cells and algae due to cells' negative surfaces, but may also capture highly charged negative ions such as orthophosphate, BUT crushed glass normally has a small negative surface charge, not a positive one, and most activated glass media have a stronger negative charge, not a positive one. Note that Fiber Clear with its 2 micron filtration claim would be able to remove most algal spores through physical filtration. If I get a chance, I may experiment in the spring explicitly measuring turbidity before and after use of Fiber Clear.
One more quick comment. If one doesn't clean their filter for 6 months or a year, then whatever organic compounds that get trapped in that filter will continue to react with chlorine and produce disinfection by-products including THMs. For low bather load pools this usually isn't a big problem, but for commercial/public pools or other situations with higher bather load it would be better to backwash or clean filters more frequently to remove the organic precursors (well, the ones that are slower to react with chlorine since that will be what is left).
In fact, I'm doing some experiments in my own pool having THMs measured at different points in time during the swim season. It's not cheap at $130 per test through the professional water testing laboratory that does most of the Northern California water district testing. I also used tap water before and after a water filter as controls and confirmed that the water filter completely removed all THMs (to the measuring limit) and I tested the pool water during the worst-case at the end of the season with a sample taken near my wife at the end of her swim. I'll also be testing to see if aerating the water reduces THM content. At least for chloramines I know they are always < 0.2 ppm from my own FAS-DPD testing and that it's likely to be mostly monochlorourea.
SOURCES OF CHLORINE DEMAND
You make the assertion that most chlorine demand is due to oxidizing organic matter rather than from breakdown from UV in sunlight. While this is very true in the moderate to higher bather load commercial/public pools, it is most definitely not true in properly maintained outdoor residential pools that are typically low bather-load unless they are uncovered and have a lot of blown-in organic material. All one needs to do is measure the overnight chlorine loss accurately, say with a FAS-DPD chlorine test, and compare that to the loss during the day, adjusting to a common time (i.e. scale to a "per day" equivalent loss rate). There are tens of thousands of residential pool owners on several pool forums almost all of whom are using Taylor K-2006 or equivalent kits (such as TFTestkits TF-100) and virtually all of them have minimal overnight chlorine loss and much larger daytime chlorine loss. However, such pools are properly maintained using an appropriate FC/CYA ratio, something that is not the case in many residential pools using Trichlor where the CYA builds up over time. Looking at 12-hour intervals in the well-maintained pools, for example, it's comparing a nighttime < 0.5 ppm (as low as 0.2 ppm) vs. a daytime 1.0 to 2.5 ppm depending on sunlight exposure and FC and CYA levels. You also need to consider the fact that chlorine oxidizes cyanuric acid as well where for every 1 ppm CYA drop there is around 3 ppm FC consumed. This alone contributes 0.2 to 0.5 ppm FC per day (usually on the lower side for most pools). Finally, the chlorine demand in equivalent bather-load indoor residential pools is far lower just as it is in pools with opaque pool covers.
You aren't the first one to make this claim that organics in a pool account for most of the chlorine demand even for residential pools. Orenda Technologies who make enzyme and phosphate remover products also told me that even in residential pools that use of their products significantly lowered chlorine demand. I completely believe them because most residential pools use Trichlor pucks/tabs and have the CYA level rise over time such that algae can begin to grow faster than chlorine can kill it. Or they have saltwater chlorine generator systems where the FC/CYA ratio target is too low. At first, the situation appears to be a higher chlorine demand, but shocking the pool kills off the algae until the next cycle begins anew. Eventually, even shocking isn't enough and the water starts to turn dull, then cloudy and then a full-fledged green algae bloom (specific sequence depends on type of algae). This is exactly what happened to me with my own pool 8 years ago using Trichlor pucks in a floating feeder and is what pushed me to learn pool water chemistry. The reason for stabilized chlorine leading to these problems is based on the chlorine/CYA relationship that is known science since at least 1974 as described in this paper. The active chlorine (hypochlorous acid) level is roughly proportional to the FC/CYA ratio (derivation of this approximation is in this post.
Anyway, back to the Orenda experience which I write about in detail in this post. The bottom line was that in spite of my having 3000+ ppb (3+ ppm) phosphate levels, the use of a phosphate remover to remove phosphates (verified by a test kit to within 125 ppb phosphate level) and the use of enzymes to oxidize organic matter, my daily chlorine demand did not change at all from the already low level prior to this treatment. There is absolutely no question that at high phosphate levels and without any other algaecide such as 50 ppm Borates, my pool would be very reactive IF the chlorine level (FC/CYA ratio) got too low (roughly below 5%), but maintaining the FC/CYA ratio such that chlorine kills algae faster than it can grow regardless of nutrient level means there is virtually no chlorine demand from algae -- one simply kills any algae dropping into the pool faster than it can reproduce.
As for organics, most residential pools have very low bather load. One person-hour in a pool generates an approximate chlorine demand from sweat and urine in a 15,000 gallon pool of around 0.075 ppm though this is dependent on the level of activity with heavier swimming being double that or around 0.15 ppm. It also depends if you have children urinating in the pool which is a very high demand (1 fluid ounce of urine in 15,000 gallons has a chlorine demand of around 0.05 ppm; 1 cup would be 0.4 ppm chlorine demand). A humorous account of why I know this is in this thread. The primary source of organics in an uncovered outdoor low bather-load residential pool is from material such as leaves and especially pollen blowing into the pool.
So while having some form of supplemental oxidation is important for commercial/public pools and probably for indoor residential pools since they don't have the benefit of UV from sunlight (and have worse air circulation), it is not as critical for outdoor residential pools that can be maintained properly using chlorine alone. I spend $15 per month on 12.5% chlorinating liquid and a small amount of acid from my local pool store to maintain my pool shown here and here. I have an oversized cartridge filter I only need to clean once a year. I have winter rain overflow for roughly 50% dilution (since there is virtually none during the swim season with no rain and no backwashing/cleaning). There is no change in chlorine demand from the end of one season to the start of the next with a cartridge cleaning in between (meaning that the buildup of organics is smaller than 0.2 ppm FC per day). Prior to the more recent (unnecessary, but interesting) experiments and after the initial Trichlor fiasco I used no flocculants, clarifiers, enzymes, phosphate removers, or other products -- today, I only plan to keep 50 ppm Borates in the pool solely as insurance for missing chlorine dosing. This same type of maintenance is being done with tens of thousands of pool owners at Trouble Free Pool and The PoolForum though most have higher chlorine demand than my pool since they do not use mostly opaque pool covers, but we're still talking about 1.5 to 2.5 ppm FC daily demand in most cases.
You correctly indicate that a key component to lowering the rate of pH rise is to lower the output level or on-time of the chlorine generator which can be done if one lowers the chlorine demand. There is more than one way to do this, however. For properly maintained pools using appropriate FC/CYA ratios to prevent algae growth, the use of phosphate removers isn't going to help except as an insurance policy in case the chlorine level gets too low. For high bather load pools, supplemental oxidation including ozone, enzymes, non-chlorine shock will clearly help lower chlorine demand. However, for typically low bather load residential pools, such systems won't lower chlorine demand since it is primarily from chlorine breakdown from the UV in sunlight. Increasing the CYA level in the pools will protect the chlorine better and reduce chlorine demand even if one raises the FC level to keep the FC/CYA level constant. Some forum members did specific experiments that proved that there was lower chlorine loss from sunlight with a big drop going towards 80 ppm (100 ppm saves even more) in spite of higher FC levels. Having 4 ppm FC with 80 ppm CYA was a reasonable sweet spot. In addition, especially if the FC gets lower, one can use 50 ppm Borates in the pool as an algae inhibitor, but also as a pH buffer that is particularly useful to less calcium carbonate scaling in the saltwater chlorine generator cell.
Note that I am not saying that phosphate removers are bad or don't work, but only that they are not the only way to prevent algae growth and keep chlorine demand low. Chlorine alone can be used if that's what one wants to do, but it must be at the appropriate FC/CYA ratio to prevent algae growth.
I completely agree with you that if you want to say that your system produces hypochlorous acid that would be accurate and perfectly fine to do so, but that's not what you say on your website. You say the following:
You are trying to make it sound like this is different than standard electrolysis of chloride to chlorine. Obviously you can say whatever you want, but if you want people on forums to stop bashing you for pseudo-science that seems to be written to deceive, then you shouldn't write stuff like that. What in the world is "non-synthetic" anyway? The chlorinating liquid and bleach products are made by the same electrolysis as is done in your Hydroxinateur -- it's just that the chlorine gas product is added to water and shipped rather than getting directly mixed with the pool water on-site.
The German DIN 19643 standard is for 0.3 to 0.6 ppm FC WITH NO CYA if no ozone is used and 0.2 to 0.5 ppm if ozone is used. You need to realize that a level of 0.2 ppm FC with no CYA has the same hypochlorous acid concentration as a pool with an FC that is about 20% of the CYA level. The reaction rates for chlorine, including the rate of production of disinfection by-products and the relative amounts of some of those products depends on the hypochlorous acid concentration and NOT on FC alone. When CYA is present, the hypochlorous acid concentration is much, much lower because most chlorine is bound to CYA and is very inactive. For oxidizing organics it is 1/100th as reactive as hypochlorous acid (see this paper) while for disinfection rates it's even less effective than that (nearly inert). It is a buffer or reservoir for hypochlorous acid so will prevent the chlorine from running out, but the FC level does not determine the reaction rate. Think of the hypochlorous acid vs. the hypochlorite ion analogy and how you were taught that hypochlorous acid is what mattered most for disinfection and the relationship between the two was a function of pH so that looking at FC alone was not wise and one also needed to look at pH. Well, the same thing is true when you've got CYA except it's even more extreme since with 3 ppm FC and 30 ppm CYA at a pH near 7.5 then around 97% of the FC is bound to CYA (around 1.5% is hypochlorous acid and a roughly equal amount of hypochlorite ion). See this post for some charts you are probably familiar with for HOCl/OCl- without CYA, but then look at the chart with CYA present that nobody shows or teaches. Since you've got lots of people working on technology in your company including chemists, they can use this spreadsheet I wrote to calculate the concentration of various chemical species when CYA is present.
AFM VS. YOUR MEDIA
Your own patent that I quoted was what mentioned AFM from Dryden-Aqua explicitly along with all of its benefits. So now you are saying that you have newer patents filed that we can't look at yet (I saw those on the Austrailian patent website) and that your media is different and superior to AFM. OK I believe you and never said your media, whatever it was, wasn't good and in fact said it was probably the best part of your whole system.
As Kim and others have mentioned, the calcium carbonate flakes can last longer and I never said that magnesium hydroxide wasn't formed, but that it would redissolve in the pool water. I wrote that it would dissolve in a few seconds so given that you say you see the particles come out of the returns then I'll grant you 10 seconds or even a minute, but obviously it can't remain in such visible form for very long or else the bulk pool water would cloud up. Like I said, you can't have it both ways with "zero turbidity" yet you are seeing visible particles streaming out of the returns which by definition is not zero turbidity. If your water is crystal clear then you don't have visible floc, by definition. I'm not saying it's impossible for the magnesium hydroxide to stay together long enough before running into some organics and that maybe they stick together to prevent dissolving (though this sounds like a stretch), but even your own patent talks about magnesium ions ALONE being divalent and having coagulating properties (by the way, calcium is also divalent). This may very well be true that this helps and would make a heck of a lot more sense -- that is, that the magnesium ions help for coagulation, not so much the magnesium hydroxide that is probably only temporary.
Unless you guys did explicit experiments with each factor separately, then you don't really know why it works so well. If you used your filter without magnesium at higher levels in the water and found that it wasn't as clear, then that points to something with magnesium. You could then compare an automatically dosed sodium hypochlorite in a magnesium enhanced pool vs. using your chlorine generator though that has 2 variables but is still useful info. If only the combination of the magnesium and the electrolytic generator led to an improvement and if this was seen even with other filters, then the magnesium hydroxide theory would hold some weight.
As for the pH of the water as it exits the cell, this isn't that high and you can prove that to yourself by measuring it. An electrolytic chlorine generator salt cell produces exactly the same result as hypochlorite added by bleach or chlorinating liquid with the only differences being no increase in salt levels, no excess lye, and having hydrogen gas. Details are in this post but the net equation is the following:
H2O + Cl- ---> OCl- + H2(g)
Water + Chloride Ion ---> Hypochlorite Ion + Hydrogen Gas
Hypochlorite ion is a weak base, but remember that you are adding it to BUFFERED pool water so the pH does not rise very much. With a TA of 100 ppm, even an increase of 10 ppm FC coming out of the return would raise the pH from 7.5 to 7.7. So as the water mixes in the cell and downstream in the pipe and the pH gets lower some of the hypochlorite ion becomes hypochorous acid. To get to a pH near 9.0 exiting the returns, you would have to be producing a little over 1000 ppm FC coming out of the return. This is obviously not what you are doing.
By "methasis" did you mean a metathesis reaction? You've got to be kidding me. That's just a reaction between two compounds that essentially swap components. In what you are probably meaning, it involved precipitation. It sounds like whomever told you this was trying to explain how magnesium hydroxide was being produced as in something like the following:
MgCl2 + 2KOH ---> Mg(OH)2(s) + 2KCl
Magnesium Chloride + Potassium Hydroxide ---> Magnesium Hydroxide (precipitate) + Potassium Chloride
except I never questioned how magnesium hydroxide could form at the cell where the other ionic species aren't relevant anyway. The hydrogen gas generation produces hydroxyl ions so the pH is higher and this directly combines with the magnesium ions present to form precipitate. I was never disputing that and notice that the other species in the above equation like potassium and chloride ions are irrelevant. What I was saying was that once the magnesium hydroxide solid is moving through the water and mixes with the acidic water from the chlorine generation plate (especially when the chlorine gas dissolves), then the pH drops and the magnesium hydroxide starts to dissolve as follows:
Mg(OH)2(s) <---> Mg(2+) + 2OH-
Magnesium Hydroxide (precipitate) <---> Magnesium Ion + Hydroxyl Ion
Whether the above happens or not depends on the concentrations of ions on the right hand side. Near the hydrogen generation plate the pH is high so the above reaction goes to the left, but away from that plate in the stream that enters the pool the pH is far lower and the reaction moves to the right, though obviously this takes time and isn't completed before existing the returns since you see particles. However, such particles continue to dissolve while in the bulk pool water and will completely dissolve because there isn't enough magnesium in the water to saturate it at pool pH and you say so in your own patent. And, repeating myself, you claim zero turbidity so can't have magnesium hydroxide precipitate or floc or else it would be visible (i.e. affect water clarity just like milk of magnesia in the extreme).
You know, it wouldn't surprise me if the only reason this whole "magnesium hydroxide as the flocculant" came up was that someone in your company saw that the particles were produced and coming out of the returns and figured they better have an explanation for that so that people wouldn't complain. Instead, they could just say that this is a side effect of having the magnesium in the pool with the generator, but that it fully dissolves and that the other benefits of magnesium far outweigh this visible artifact.
I never said that the generator was the key to your system. I only complained about how you were trying to hide what it really was, which is nothing more than a standard saltwater chlorine generator. This is not the unique part of your system. I did not say that your product used AFM, I said it used recycled crush glass LIKE AFM and then your own patent referred to AFM so I figured you might actually be using AFM. You say you aren't and have developed something superior and I believe you. As I've said before, I think this is the best part of your system and I'd bet that even without the magnesium you would have superior water quality, though perhaps much better than sand but not quite as good as when you use the magnesium. And for sure I never said that you could simply add magnesium to a salt pool (well, replacing the salt with a different salt) and you'd get all the benefits. Again, the filtration medium is key. And yes, flocculation/coagulation is important as well, but it might be the magnesium ion alone and not the production of magnesium hydroxide that clearly redissolves.
For residential pools, many oversized cartridge filters need cleaning only every 6 months or 12 months. To the degree that the amount of water you backwash is less than the amount of water drained from the cartridge filter housing, then you are right, but I never compared the two volumes exactly. I know for my Jandy CL 340 cartridge filter I clean once a year that at 25,246 cubic inches (from its dimensions) that this is 109 gallons so actual water loss from the drain may be half that (for inner dimensions and cartridge displacement volume), but then one has to add the amount used for hosing down and soaking the cartridges. How much water is used for your backwash when one goes for 6 or 12 months between backwashing?
For me, the issue is not that this system does not work, but that I wanted it presented accurately. Some people don't care if they are told inaccurate information about how something works when it does, but others do care because it makes them wonder what else might not be true -- it's an issue of trust. I am in no way trying to ding MagnaPool, but instead of trying to defend marketing info that can be misleading, I think they should look at this as feedback to be able to win over skeptics not just over whether something works, but whether you can truly trust the person and company you are buying this from (or the manufacturer who makes it, etc.).
Iam not a scientist, I only know from end user instalations Magna works, so what is the all the huff. Seems the SWG market may be worried. Like the banks were, when mortgage brokers came in to play, now mortgage brokers account for 60% of all lending here in AUS. Silly banks for not listening to its customers. I still come back to my earlier post, 1. If it reduces salinity,2. keeps water clear,3. makes water fresher whether fact or illussion, is not that a good thing. I asure you I would not be instaling it in my market if clients are going to grow green horns and destroy their pool.
Just my simple 2 cents worth in basic terms.
Ross Palmer said: