I just saw a Kickstarter campaign for a "vortex vessel" that supposedly improves tap water for drinking.

Some of the claims:

  • "[Tap water is] stuck in closed pipes where no beneficiary chemical reactions can occur"
  • "Toxins from the pipes dissolve into the water, and bacteria colonies flourish in the cracks"
  • "Chlorine was added to the water [...] not great for us"

Their product, a jug which causes a vortex:

  • "brings water back into [its] natural form"
  • "aerates and balances the water with atmospheric oxygen"
  • "starts a line of chemical reactions - evaporating chlorine, volatile organics, and other toxins"
  • "precipitating metals like manganese and iron so they don't react in your body"
  • "stripping away the metallic taste and unpleasant odor"
  • "balancing the water's pH level"

Can simple water movement really provide all these benefits? It seems like a ridiculous set of claims.

enter image description here

  • 6
    So nice to get a downvote with no comment – user46979 Nov 5 at 22:08
  • I upvoted this myself, but I would guess that a downvoter might feel that this specific claim is insufficiently-notable. – Roger Nov 5 at 22:29
  • @roger 2000 backers on kick starter means a lot of people have seen it. Perhaps over a million. – fredsbend Nov 6 at 1:58
  • @Roger has provided the best available evidence about aerating water. However that only addresses some of the quoted claims. The trouble with the rest of them is that befoure you can start deciding whether they are true or false you have to guess what they mean. For example, what "beneficiary chemical reactions" are prevented when water is in a pipe, and what is the "natural form" of water? These terms have no meaning in any dictionary or scientific text book. The problem is that, no matter what I guess, I may have guessed wrong. So if I say "I guess the writer really meant X, which is wrong" – Paul Johnson Nov 6 at 13:31
  • I changed some of the wording to exclude claims of health benefits and instead focus on tangible effects on the water itself, not what it supposedly then does in the body because that is another discussion entirely. – MichaelK Nov 6 at 14:02
up vote 18 down vote accepted

The nature of the device

First of all a clarification.

Their product, a jug which causes a vortex:

is not a jug alone and the jug doesn't cause a vortex. This a magnetic stirrer. These devices are on sale now, arguably in less attractive form factor for house hold appliances (aesthetics feelings may vary):

enter image description here

These products do create a vortex. But the vortex alludes to something else, possibly water woo as another answer calls it. See at the bottom for why "vortex" means something else.

Such a vortex will affect the water. But the claims for the product are bit on the wide ranging side.

The whole product is called "Keep Your Water Healthy with a Natural Swirling Motion". If this is indeed meant to say that there is "healthy water" and "unhealthy water" for drinking, then this becomes difficult to analyse without recurring to commonly accepted standards of safety. That is: either a water is safe to drink or not. Certain ingredients to supposedly pure water are more desirable than others. Claiming health benefits of that kind for any water is actually forbidden in Europe (a few are allowed).

The magnetism, or the glass, will not affect the water. The vortex does that and it does it by thoroughly mixing the water and all its "ingredients" together with surrounding air. That usually means most of the gases in solution will be driven out as long as the jug remains open. Therefore chlorine will dissipate, carbonic acid will, methane and other light substances, like radon. The amount of oxygen in water will increase slightly, but oxygen does not dissolve well in water.

Also of note may be the aeration for water treatment is usually not done with a "vortex", but with aerated lagoons, a carburetor and very efficiently in most households with a faucet aerator. Using small bubbles is way more efficient than just stirring it, or "making a vortex" if you prefer that language.

Water aeration

So the most interesting part that is left from the device is that it treats water with aeration. But water treatment aeration is indeed used on an industrial scale, mainly:

Many water treatment processes use a variety of forms of aeration to support biological oxidative processes. A typical example is Activated sludge which can use fine or coarse bubble aeration or mechanical aeration cones which draw up mixed liquor from the base of a treatment tank and eject it through the air where oxygen is entrained in the liquor.

Aerated water will often taste better:

Purpose of aeration
Sulfur compounds dissolved in water are not necessarily dangerous, but can give the water a bad taste or foul smell. These compounds can be removed in several ways, the most effective being by exposure to chlorine gas. However, aeration can also be effective if the amount of sulfur in the water is relatively low.
During aeration, water is pumped into a non-pressurized tank and agitated. This physically removes many of the sulfur compounds, which are then vented. Exposure to oxygen in the air also oxidizes some of the compounds, creating atomic sulfur which can be filtered from the water. Aeration is also an effective means of removing radon from water. Small tanks and ponds for keeping aquatic animals such as fish or lobsters often rely on aeration to maintain sufficient level of oxygenation in the water. This can be achieved by pumping air into the water, allowing it to bubble to the surface; or by a fountain jet agitating the water. Both these methods create an agitated, large amount of surface area between the water and the air, thus allowing transfer of gases.
Wave action on the shores of large bodies of water can provide aeration of the water in the vicinity, thus providing enhanced oxygenation which can benefit various aquatic lifeforms.

That last paragraph may be what the claimants mean with "back to its natural state". However, that term is of course quite meaningless. This is natural water as well, and the jug hopefully does not transform the water we shall put into it into that:

enter image description here (Source WP: Puddle)

While you can remove iron with oxidation from Fe2+ to Fe3+, this will precipitate as brownish coloured sludge and needs to be filtered out. "Removing iron" with this device will result in either no effect at all, as a user will drink the sludge, or in discolouring precipitation on the glass. To remove it, a user will need an additional filter or distill the water.

Aeration is nice, but not that far reaching and effective as claimed for the product. The most effective use of aeration is done already in conventional water treatment facilities, your home water faucets. Getting additional benefits requires the use or other techniques or additional treatments, as outlined in Antonio Gil & Luis Alejandro Galeano & Miguel Ángel Vicente: "Applications of Advanced Oxidation Processes (AOPs) in Drinking Water Treatment", Springer, Cham, 2018.


The vortex

From the Kickstarter site Keep Your Water Healthy with a Natural Swirling Motion:

March 2015 – Ze'ev and Shay find some documents detailing the powerful effects of natural swirling motion in water, originally discovered by Victor Schauberger, a 19th century Austrian scientist.

Now, Schauberger was primarily a forester and his claims on the effects of vortices on water were apparently the inspiration for this device to be sold? Then the manufacturers do quite a goof job of at least associating actual science to these decidedly pseudoscience origins of recreating 'living water'. This is just an appeal to the esotericist scene, focusing on bogus water treatments.

Great invention. You guys should look up Alick Bartholomew. He also invented something similar and wrote a book about it called " The Story of Water". Also look up " The Shauberger Keys". The key is the spiralling motion of the water, it energises cells in the body! Good Job guys
MAYU WaterCreator: Thanks Simone! Great info. We were originally inspired by Schauberger's "Comprehend and Copy Nature"

The claims from the question in available light

  1. "[Tap water is] stuck in closed pipes where no beneficiary chemical reactions can occur"
  2. "Toxins from the pipes dissolve into the water, and bacteria colonies flourish in the cracks"
  3. "Chlorine was added to the water […] not great for us"
  4. "brings water back into [its] natural form"
  5. "aerates and balances the water with atmospheric oxygen"
  6. "starts a line of chemical reactions - evaporating chlorine, volatile organics, and other toxins"
  7. "precipitating metals like manganese and iron so they don't react in your body"
  8. "stripping away the metallic taste and unpleasant odor"
  9. "balancing the water's pH level"
  1. Tap water is moving through the pipes to your home.

  2. Toxins can be released from the pipes, but that is mostly lead in old pipes. A heavy metal compound the aerator cannot influence. As the aerator mainly acts on volatile compounds these "toxins" would have to be volatile compounds found in the pipes. The company alludes to bacteria but fails to address the consequences of this or how that relates to their product. The WHO report below cited by the company runs counter to this bacterial allusion.

  3. Chlorine is added to water supplies because it is much greater for us than drinking water that is microbially contaminated. Not the least because of chlorine, the bacteria from claim2 do not flourish in the pipes.

  4. Water's "natural form" is: a fluid aggregate at room temperature and at atmospheric pressure equivalent at sea level. Obviously the device does little to change that. All other meanings of "natural" have to appeals to esoteric concepts. Given the other claims and the intended design goal for the device it seems to equate "natural" with "clean".

  5. Yes, the device aerates water, but it does so way less efficiently then any device that causes bubbles. The "balance" is again an esoteric concept that is meaningless without further definition.

One very peculiar explanation when looked at that on an industrial level is in "Factors Affecting Low-Speed Surface Aerator Performance":

The zone of influence of a surface aerator can be extended by adding ancillary equipment to the system. Mixing devices generally consist of lower mixing impellers or draft tubes. These devices may improve circulation but often have little influence on aerator SAE. However, in some instances, there may be negative effects on SAE as in the case of supplementary down-pumping impellers in very deep tanks. Draft tubes may also have a negative impact if improperly designed so as to increase friction head. The use of baffles in circular or square tanks is often prescribed for mixers to avoid vortexing and to promote greater system turbulence. Their use for surface mechanical aeration is not often seen in practice.
James A. Mueller & P.E. William C. Boyle& P.E. H. Johannes Pöpel: "Aeration: Principles and Practice", CRC Press: Boca Raton, London, 2001, Ch.5 Surface and Mechanical Aeration, p 242.

  1. Well, true in a sense. Although evaporation is not a chemical process, volatile compounds are volatile because they dissipate from the water as soon as they are added. So giving them several benefits of low standards: the device accelerates chlorine evaporation, but slower than boiling the water.

  2. Oxygenation of water will facilitate oxidation of iron and manganese. Undeniably true. But these will then go out of solution; but they will not evaporate but concentrate as either sludge or will be kept in suspension as long as the vortex is active. Without a filter for the particles a user will need to let it sit still and go flat again so they can form a sediment or a user will drink the iron and manganese anyway.

  3. Not all public water supplies do taste metallic and smell unpleasant. It depends on the exact nature of the substances present that do cause the undesirable features to determine whether they will be removed or not. If the smells and tastes come from those that aeration can affect positively it's a win, if the metallic taste comes from uranium or mercury and the smells from non-volatile organic compounds it's a loss.

  4. "Balancing" a water is again a meaningless scale. Canned soft-drinks range from 2–9 pH and the stomach can handle this well. Even pressure oxygenated water has so far failed to provide significant "benefits" so this stirred version will have an even harder time to provide any "benefits". A raised pH of water is mostly the effect of driving out the carbonic acid, as "Carbon dioxide is the most common cause of acidity in water" and gaseous oyxgene molecules do not influence pH at all.

What do competitors to the Mayu vortex vessel say?

Oxygenated water is oxidative water; it is not healthy to drink! When you add oxygen to something, you oxidize it. If you add oxygen to alkaline water, you will neutralize it and lose the health benefits.

(That is of course bogus as well, but gives a nice contrast to the claims from the manufacturer)


These claims for the product are about taste, which is verifiable and works. Boil the water to get rid of microorganisms, filter it to get rid of bigger size contaminants, if they are present, than aerate it again to improve the taste. That is the one application this device is really good for. In a combined chain of other devices.

These claims for the product are about "healthier water option" ("Much healthier Water – You know the stuff You're Mostly made of") by treating it in caraffe right before immediate unfiltered consumption. These are largely bogus claims with no scientific literature to back them up.

But don't they cite scientific literature? "The premise is simple and backed by prominent scientific literature."? Like "K ,Taricska, J. R., Wang, L. K., Hung, Y.-T., Li, K. H., Huang, J.-C., Shang, C., Scovazzo, P. (2006). Advanced Physicochemical Treatment Processes. Advanced Physicochemical Treatment Processes. https://doi.org/10.1007/978-1-59745-029-4" on their own website with the claim: "As a result, water aeration may be the single most important water treatment process used in the 21st century."?

They do that. They cite this one sentence from a reputable source correctly. But they quote it out of context and in a misleading way. Following up that paper reveals the same sloppiness the manufacturers put on display when they try to convince the buyers with "When water is kept flowing it aerates, like a fine wine exposed to air." How is this comparison with wine from the wine connoisseurs point of view:

However, too much oxygen can lead to oxidation, the degradation of wine due to an abundance of oxygen. This can happen during the actual winemaking process or even after the wine has been bottled. Basically, all oxygen needs is a simple catalyst for the reaction to occur. Anthocyanins and phenols, two components of wine, are very susceptible to oxidation. When oxidation takes place, the wine’s pigmentation will decrease and loss of aromas and flavors will occur. Think of an apple that’s been sliced and left out too long; the abundance of oxygen causes the flesh to brown, the aromas to dissipate and the flavors to disappear. Same thing goes for oxidation in wine. (What Is Oxidation And What Is It Doing To My Wine?)

Back to the Taricska-paper:

Falling Water Units (commonly used in water treatment)

Surface Aerators (commonly used in the wastewater industry) 1. Mechanical surface aerators—water surface is mechanically mixed to increase water to air interface. a. Brush: a series of circular brushes partially submerged are rotated through the water surface to cause turbulence. A support structure is required to suspend the brushes over the water. b. Floating: Floating aerator pumps the water from beneath it up through a draft tube to the surface, which disperses water into the air.

Submerged Aerators (commonly used in the wastewater and water industries)

The magnetic stirrer falls clearly into the surface aerators.

Taricska applies these to industrial applications not readily applicable to the product at hand:

Although taste and odor applications are most common, there are many other tastes and odors that simply cannot be removed by aeration alone, which may explain why so many early plants were abandoned.

The removal of iron is accomplished through sedimentation and filtration of the precipitated iron. Theoretically, 1 mg/L of O2 will oxidize about 7 mg/L of Fe2+.
Manganese concentrations greater than 0.3 mg/L in water will result in dark brown staining. Oxidation will convert the manganese from Mn2+ to Mn4+ when the pH is above 9. Below a pH of 9, the process is negligibly slow. When tray aerators are utilized for aeration and trays become coated with manganese oxides, the removal is accomplished first by adsorption on accumulated oxidation products (Fe2O3 or MnO2) fol- lowed by slow oxidation.

And probably the kicker:

2.5. Aesthetic or Decorative Aeration Fountains are an attractive way to display product water. They can also be functional particularly for taste and odor improvement. Also, they conjure positive associations for many onlookers.

Aeration restores oxygen to water, making the water taste better but it also increases corrosiveness, by increasing the CO2 in the water (resulting from the oxidation of organic matter to CO2). Therefore, there is often a trade off between benefit and detriment

Some take away points from the World Health Organization: "Water, Sanitation and Health Department of Protection of the Human Environment", Geneva, WHO/SDE/WSH/02.07:

Aeration Availability and Practicality: Moderate; Technical Difficulty: Low; Cost: Low; Microbial Efficacy: Low
Aeration (oxygenation) may have synergistic effects with other water treatments, such as solar disinfection with sunlight or with other processes that may oxidize molecular oxygen.
Studies also show that dissolved oxygen in the water contributes to bacterial inactivation, with much greater reductions of E. coli and enterococci after 3 hours in oxygenated water (~6 log10) than in anaerobic water (<2 and <1 log10, respectively) (Reed, 1996). In subsequent studies total and fecal coliforms were inactivated by >3 log10 in 6 and 4 hours, respectively, in aerated water and by #1.5 log10 in anoxic water or water kept from sunlight (indoors) (Meyer and Reed, 2001). Therefore, aeration of the water by mechanical mixing or agitation is recommended before solar treatment in bottles. The combined process of oxygenation (aeration) by mixing, followed by solar radiation exposure for several hours in a clear plastic bottle is also referred to as solar photooxidative disinfection of SOLAR. Enteric bacteria inactivated by the SOLAR or SODIS process do not appear to regrow or recover their infectivity. Water Aeration (oxygenation) –– Increased oxygen content of the water by agitating (shaking) for several minutes in contact with air prior to sunlight exposure increases microbial inactivation when sunlight is allowed to penetrate water in clear bottles (SOLAIR or SODIS processes)

This is again comparing aeration of the water together with another method for improving water quality. The company talks about the "microbes that flourish in the cracks" of the water pipes? What the company quotes is of course just half of the story:

4.9 Aeration Aeration of water alone is simple, practical, and affordable, especially if done manually in a bottle or other vessel. Aeration of water has been practiced since ancient times and was believed to improve water quality by "sweetening" and "softening" it (Baker, 1948). It was later discovered that aeration indeed oxygenated anaerobic waters and that such a process would oxidize and precipitate reduced iron, manganese and sulfur, as well as strip volatile organic compounds, some taste and odor compounds, and radon. However, there is no evidence that aeration for brief time periods (minutes) has a direct microbiocidal effect. However, aeration of water introduces oxygen, which can cause chemical reactions, such as precipitation in anaerobic water containing certain dissolved solutes, and which can contribute indirectly to other process that may lead to microbial reductions. In addition, studies suggest that aeration has a synergistic effect with sunlight and heat on disinfection by solar radiation of water held in clear bottles. The mechanisms of this effect are not fully understood. However, they may involve conversion of molecular oxygen to more microbiocial chemical species by photooxidation reactions with microbial components or other constituents in the water, leading to photodynamic inactivation. Further studies of the ability of aeration to inactivate microbes in water either alone or in combination with other agents needs further study. Currently, there is no clear evidence that aeration alone is capable of appreciably and consistently reducing microbes in water.

Harder data – from the manufacturer

Skeptics were requesting harder data. The manufacturer claims this:

Water swirling in MAYU vessel (without the cap on) make the chlorine evaporation from the water 2,400% faster. The swirling motion balance the dissolved oxygen level in fridge dispensers for example, from 20.6% to 94.7% in less than 10 minutes. a process that will take days in standing water. These facts, after you learn the mechanisms that works behind them are cool, one can get rid of chlorine without buying filters every X months (and producing more plastic waste) But what really amazed me was organoleptic effects, how subtle the human senses are… people can feel the difference in taste and mouthfeel of the water after this simple manipulation. on our blind taste tests, we gave over 100 people, two cups of the same water, one strait out of the tap, one swirled for at least 10 minutes (with the cap off) 83% of them sensed the difference and preferred the water that was moving over the same water that was standing.

enter image description here Image sourced from regular manufacturer website https://mayuwater.com/aerate/

Unfortunately, the maker really doubles down on these 'facts' (not independently confirmed):

1 Purify Restart your water, clean it leaving only H2O 2 Aerate Swirling your water increases the gas transfer by 6000% 3 Mineralize Supplement the pure H2O with essential minerals.

As shown above item 1 is so much of an overstatement, it has to be called a lie. The numbers for item 2 seem absurdly high. They also do not match their own numbers given in the forum section of the kickstarter site. And, mineralize? How should that be even possible by aeration alone? Well, it isn't. What seems a bit hard to find is that the way they arrange the quotes and testimonials from doctors does make it look as if. But really they also want to sell mineral/salt tablets to add to their finished product. Another source of steady revenue…

Another instance of false advertising is found in their allusion to microplasic (not touched by aeration), and links to "from the press": U.S. Drinking Water Widely Contaminated (unclear connection), America’s Tap Water: Too Much Contamination, Not Enough Reporting, Study Finds, USA today: 4 million Americans may be drinking toxic water and may never know, CNN: 5,300 U.S. water systems are in violation of lead rules (lead will be nicely vortexed and just remain), BBC: Why America's drinking water crisis goes beyond Flint (again, scary news about lead in water, not affected by the device).

Direct quotes from representatives of the manufacturer

Arjan Kroonen: I'm worried about the magnetic radiation you are using to move the water. I understand it is good to clean the water using movement but the magnetic poisoning of the water will mean I need to demagnetize the water before drinking it!
MAYU: Thanks for the comment Arjan!

Any stretch goals ?
MAYU: Hi Lily, no, MAYU removes volatile compounds such as TCE, THM, H2S, etc and Chlorine. Since Flouride (I think you were referring to the ion of Fluorine which is called fluoride) is not volatile, we do not remove it. For complete protection from everything, MAYU recommends using a powerful purification method such as reverse osmosis or thermal distillation. These will definitely remove fluoride along with other baddies.

Limestone or other heavy water would still need to be filtered out. Limestone doesn't exactly evaporate.
Mayu: you're absolutely right. Limestone is dissolved Calcium Carbonate which does not evaporate. As we mentioned in other places here as well, MAYU recommends using Reverse Osmosis or distilled water prior to aerating and remineralizing the water.

Concerning heavy metals: What do you recommend doing in order to get rid of them, when drinking tap water?
MAYU: For optimal water quality, we recommend you keep using it or some other treatment option. MAYU will definitely improve taste after carbon (by aerating volatile organics and raising the pH) The easiest way to get rid of lead and other heavy metals is Reverse Osmosis. The problem with it is that it also removes the good stuff- not only the bad. https://www.mayuwater.com/purify/

MAYU: Lead- no- aeration does not remove heavy metals

MAYU: Pharmaceuticals- many of the components are volatile organics. MAYU's gentle aeration removes volatile organics.


From another forum:

Hi, Gilad from MAYU here. Thank you for the compliments- we also believe this product has a captivating quality.
As to the pseudoscience claims - we do not write anywhere that we clean the water entirely but:
Buying a lab stirrer could probably give you a similar effect but: […]

Guys- this is a product people worked very hard to develop and produce- we want it to be pretty and also functional and useful. If you like it- good for you- if you don't it's also ok. Making bold claims about pseudoscience and quackery are not fair.

Summary

This is not a completely useless device. A few of the testable claims for its actions are true in principle, although exact testing might indicate a problem of scale when using it on fairly clean public water to begin with and not as a device in a chain of applications. The effect of simply stirring the water is very small. On the positive side: the water will probably really do taste better, it will remove unwanted volatile compounds dissolved in water and increase the wanted volatiles (O2 and CO2). To a certain extent, that is. On the negative side: all non-volatile compounds will remain and are at best oxidised slightly. As not enough bacteria (from municipal water supplies) are present to really break down the complex organic molecules that are perhaps present. Inorganic heavy contaminants will not change significantly.

The advertising for the device is appealing to esoteric tastes of "living water", "complex water", "natural water" etc. The claims for the product are too far reaching on first sight and not really corrected in an as obvious way as the headlines scream. The company is actually better than Apple in bringing to market a magnetic power plug instead of removing it and still selling a device with a use serviceable battery.

The way they mix science with pseudo science and gibberish and lies leaves a much more unpleasant after taste than any water treated with that stirrer.

  • I think not every single claim (like those running against basic principles) is really worth to be tackled with refs, to keep the answer short. If anyone thinks different, feel free to edit directly, or criticise the answer here in comments. I have no objections to hitting the character limit on this one and add more refs. – LangLangC Nov 7 at 14:53
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    You should excise the part about water not being able to be healthy. Individual health is just one of the uses of "healthy" as an adjective, another being "beneficial to one's physical, mental, or emotional state : conducive to health," hence the use of the term when talking about a "healthy diet" or a "healthy lifestyle." – PoloHoleSet Nov 7 at 15:46
  • @PoloHoleSet The quoted claims do not state anything about the water becoming "healthy" by the device. That was written by OP in an earlier version of the post, but that has been removed since the quoted claims do not make any such statements. – MichaelK Nov 9 at 14:34
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    @MichaelK - I'm referring to the reference that LangLang has in the answer where he questions the semantic/linguistic accuracy of producers of the product making that statement, based on the idea that water is not healthy because it's not a living thing. – PoloHoleSet Nov 9 at 16:08
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    @MichaelK - Did you look at the Kickstarter page that was linked? It's the title of the page, for goodness sakes - "Keep Your Water Healthy with a Natural Swirling Motion", and then in the start of the descriptions or claims, the first section is titled "Much Healthier Water." Are you actually saying that does not constitute making a claim? – PoloHoleSet Nov 9 at 16:10

Plausible.

This is a form of water aeration.

To cite a nice-looking site on the topic of water aeration:

EFFECTIVE AGAINST: Aeration water treatment is effective for management of dissolved gases such as radon, carbon dioxide, some taste and odor problems such as methane, and hydrogen sulfide, as well as volatile organic compounds, like MTBE or industrial solvents. It is also effective in precipitating dissolved iron and manganese. Aeration raises the pH of water.

NOT EFFECTIVE AGAINST: Aeration is not effective for removal of heavy metals, or pathogenic (disease-causing) organisms like bacteria and viruses.

This seems to be generally confirmed by this page from the United States Environmental Protection Agency.

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    The device does not appear to be actually aerating. There is no apparent source of air being introduced. The bubbles are probably dissolved air. – Daniel R Hicks Nov 5 at 21:39
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    @Oddthinking - In a closed bottle? – Daniel R Hicks Nov 6 at 0:08
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    @DanielRHicks: Wait, it is closed? (Checks video: Yep, about half the time.) There goes the claim about getting rid of the chlorine! – Oddthinking Nov 6 at 0:15
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    There are two kinds of plausibility at stake here. It is plausible that aerating water reduces the amounts of certain contaminants in the water. But, since domestic water supplies contain only insignificant amounts of them, it is not clear that a significant improvement in health is plausible (which is claimed). – matt_black Nov 6 at 10:01
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    @PaulJohnson or by getting it from a faucet that has an aerator screen installed. – phoog Nov 6 at 18:00

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