Magnesium Filtration

[wozzie]

We're planning on buying a new pool and have heard about the Magnapool filtration system, which supposedly uses no chlorine, is better for your skin than harsh chemicals, etc. I'd be interested to hear about people's experiences with this or similar types of systems. Are the claims true or is it all marketing hype?

[waterbear]

We're planning on buying a new pool and have heard about the Magnapool filtration system, which supposedly uses no chlorine, is better for your skin than harsh chemicals, etc. I'd be interested to hear about people's experiences with this or similar types of systems. Are the claims true or is it all marketing hype?

The system is not sold in the United States from what I can see. According to their website the only N. America location to purchase the system is St. Croix.

It uses milk of magnesia (magnesium hydroxide) as some sort of flocculant and uses 100% recycled fused silicon dioxide in a sand filter, claiming it is better than sand. Here is the interesting part. Silicon dioxide is also called silica, which is another name for sand! So they are selling you a sand filter with sand and saying it's better than sand! It gets even better, fused silicon dioxide is also called amorphous silica or glass. So they are selling you a glass filter medium that is still basically a manufactured sand.

Snake oil? You be the judge but I think it's a safe bet!

As far as sanitizing the water their website says that their system uses potassium chloride and magnesium chloride with a machine called a Hydroxinateur that produces "non synthetic chlorine". (Someone please tell me what synthetic chlorine is!) In other words it's a salt water chlorine generator system that uses potassium chloride and a LOT of hype! Potassium chloride can be substituted with any SWCG with no problems, btw. It just costs a lot more than sodium chloride.

Very expensive snake oil.

Net result is a chlorine pool!

Don't think it's not! It is!

The commercial system included pH and ORP controllers. Definitely a SWCG system.

Before you spend the money on it I will gladly sell you some magnets to improve your water quality, a few copper rods to drop in the water to sanitize it, and some swamp land in the Everglades!

[quantumchromodynamics]

It's just a typical salt system. They are just trying to be clever by calling the cell a "hydroxinator" because it creates hydroxide just like every other salt cell. They are trying to convince people that the hydroxide is the key benefit.

Their claim of creating "magnesium hydroxide" is nonsense. The concentration of hydroxide in the general water is determined by the pH. Their claim of creating some sort of special chlorine is also nonsense. Chlorine is constantly changing from hypochlorous acid to hypochlorite to chlorinated cyanurates. The amount of time chlorine spends as each type depends on the pH and the cyanuric acid concentration.

[DreyfusDr]

We're planning on buying a new pool and have heard about the Magnapool filtration system, which supposedly uses no chlorine, is better for your skin than harsh chemicals, etc. I'd be interested to hear about people's experiences with this or similar types of systems. Are the claims true or is it all marketing hype?

The system is not sold in the United States from what I can see. According to their website the only N. America location to purchase the system is St. Croix.

It uses milk of magnesia (magnesium hydroxide) as some sort of flocculant and uses 100% recycled fused silicon dioxide in a sand filter, claiming it is better than sand. Here is the interesting part. Silicon dioxide is also called silica, which is another name for sand! So they are selling you a sand filter with sand and saying it's better than sand! It gets even better, fused silicon dioxide is also called amorphous silica or glass. So they are selling you a glass filter medium that is still basically a manufactured sand.

Snake oil? You be the judge but I think it's a safe bet!

As far as sanitizing the water their website says that their system uses potassium chloride and magnesium chloride with a machine called a Hydroxinateur that produces "non synthetic chlorine". (Someone please tell me what synthetic chlorine is!) In other words it's a salt water chlorine generator system that uses potassium chloride and a LOT of hype! Potassium chloride can be substituted with any SWCG with no problems, btw. It just costs a lot more than sodium chloride.

Very expensive snake oil.

Net result is a chlorine pool!

Don't think it's not! It is!

The commercial system included pH and ORP controllers. Definitely a SWCG system.

Before you spend the money on it I will gladly sell you some magnets to improve your water quality, a few copper rods to drop in the water to sanitize it, and some swamp land in the Everglades!

[PoolGuyNJ]

The use of potassium chloride interests me greatly. I have used it as an ice melt, as a table salt alternative for those on low sodium diets, and have heard but not seen any data that might indicate it might be easier on certain pool surfaces such as Oklahoma flag stone coping. Has anyone got any references they can point me to?

Scott

[DreyfusDr]

The use of potassium chloride interests me greatly. I have used it as an ice melt, as a table salt alternative for those on low sodium diets, and have heard but not seen any data that might indicate it might be easier on certain pool surfaces such as Oklahoma flag stone coping. Has anyone got any references they can point me to?

Scott

Scott,

I am an insider from the Magnapool company in Australia.

I have no data on potassium chloride and soft stone ,but would suspect that it acts similarly to sodium chloride in that it crystalizes to hard granule.

the MAGNAPOOL blend contains both KCl and MgCl2

MgCl2 is likely to be less problematic in that it is hydroscopic and won,t form a hard salt crystal.

In Australia where salt chlorination was pioneered en mass some 40 years ago and over 700,000 or 90% of pools have swg,s it has been quite common practice to use a sealer on soft stone, and a lot of soft sandstones are used there.

I would not use any electrolyser system without first sealing the stone.

this appears to be an issue in the united states and no doubt Australia went through the same problem many years ago before a solution was found.

[waterbear]

Scott,

I am an insider from the Magnapool company in Australia.

I have no data on potassium chloride and soft stone ,but would suspect that it acts similarly to sodium chloride in that it crystalizes to hard granule.

the MAGNAPOOL blend contains both KCl and MgCl2

MgCl2 is likely to be less problematic in that it is hydroscopic and won,t form a hard salt crystal.

In Australia where salt chlorination was pioneered en mass some 40 years ago and over 700,000 or 90% of pools have swg,s it has been quite common practice to use a sealer on soft stone, and a lot of soft sandstones are used there.

I would not use any electrolyser system without first sealing the stone.

this appears to be an issue in the united states and no doubt Australia went through the same problem many years ago before a solution was found.

I find it interesting that you admitted in a moderator report that you sent (because you did not like the comments I posted above) that the unit is a SWCG but no where on the magnapool website does it say this. Why not just be upfront on the website? The website implies that the magnesium filtration is what is sanitizing the water yet your unit is simply generating chlorine just like your competetors SWCGs, is it not? Here is a quote on how the system works directly from your website:

"...Second, the MagnaPool Hydroxinateur generates non-synthetic chlorine as a natural by-product of hydroxination, a process that mimics the production of non-synthetic chlorine that occurs within our own bodies to fight bacteria and disease....

Traditional salt-water pools contribute to dangerously high salinity levels in the environment, while traditional chlorine pools dose chemically laden wastewater back into the water cycle. When used properly, as it was designed, a complete MagnaPool system wastes no water...

.Unlike traditional pool wastewater, which contributes to environmental issues, your MagnaPool's backwash water can safely be used to water your lawn and garden (when diluted 5:1)..."

The website compares how the Mangapool system works to how the oceans remain clean but this is a fallacy. No where in the ocean is chlorine being generated by electrolysis and no where is bacterial processes breaking down waste matter in a chlorine sanitized pool yet bacterial filtration is a major part of the ocean's ecosystem.

How is the 'chemically laden" wastewater from a standard Salt pool different than the wastewater from a magnapool. In my own salt pool all I ever have to add are salt, acid, and calcium because I have very soft fill water. I need nothing else.

Also, diluting the water from any salt pool 5 to 1 will dilute the salt low enough, even for the Australian SWCGs that run at about double the salt concentration of US units, down to the low end of the levels found in "brackish" water and fresh water (fresh water is below 500 ppm and brackish is between 500 and 30000 ppm. If the salt level in a pool is 6000 ppm then a 5 to 1 dilution brings it to 1200 ppm which is the low end of the brackish range. A salt level of 2800 ppm diluted 5 to 1 produces essentially fresh water with a salt level of under 500 ppm)

Your product does provide an additional twist over other SWCGs and that is the use of magnesium hydroxide as a flocculant. If you could post any studies done to show it's benefits it would be most interesting but there is nothing on the website that backs up this claim.

So, my question to you...Is this system a SWCG or that uses a sand filter with glass sand or not and is chlorine (hpyochorous acid/hypochlorite ion) the sanitizer produced? IF so why all the pseudoscience about the ecosystems on the oceans on your website?

As far as magnesium chloride in salt water pools, Australia's Lo-Chlor has had a product called Salt Cell Protector plus for quite a while now that is a magnesium chloride additive for salt pools..

It is distributed in the US by Horner and the purpose was to favor the formation of magnesium carbonate "scale" over calcium carbonate scale since the magnesium carbonate is softer and more readily removed from the salt cell plates and pool surfaces that calcium carbonate.There is actually sound chemistry behind this.

Finally, I refer you back to the OP of this thread:

[quote name='wozzie' date='14 November 2010 - 11:59 PM' timestamp='1289797197' post='119001']

We're planning on buying a new pool and have heard about the Magnapool filtration system, which supposedly uses no chlorine, is better for your skin than harsh chemicals, etc. I'd be interested to hear about people's experiences with this or similar types of systems. Are the claims true or is it all marketing hype?

To answer that question it is marketing hype and snake oil since the system does use chemicals and chlorine, does it not?

Last time I checked potassium chloride and magnesium chloride are chemicals, aren't they?

[chem geek]

Look at this post as well as the rest of this thread for some info from the manufacturer and distributors. The magnesium content is less than 500 ppm which means that the bulk of the remaining salt levels (total of around 3000 ppm) is potassium (and chloride, of course). That's a good thing because magnesium sulfate is much worse than sodium chloride on soft stone. See this paper for more details. So while magnesium chloride might be less problematic, magnesium sulfate is far worse. Of course, this all depends on the sulfate concentration of the water which will usually be low unless one uses non-chlorine shock (MPS) since that is high in sulfate or one uses dry acid (sodium bisulfate) or sulfuric acid for pH control.

The magnesium hydroxide claim of flocculation is pure bunk. The solubility of magnesium hydroxide in water is determined by the K_sp which is 1.5x10^-11. Even if one assumed a magnesium level at 3000 ppm salt equivalent (rather than the < 500 ppm that is actually there), magnesium hydroxide would only begin to be over-saturated and theoretically precipitate or flocculate when the pH was above 9. In other words, there may be some formation of magnesium hydroxide near the hydrogen gas generation plate in the electrolytic cell since the pH is high there, but just a little away from that plate where the main flow of water occurs and where mixing with the acid water from the chlorine generation plate occurs the pH gets back to normal, especially with the pH buffering. So any magnesium hydroxide that was briefly formed will fully dissolve in water.

I don't mind a manufacturer making valid claims such as using potassium instead of sodium so that one can water plants with less salt burn effects or in using some magnesium for some "salt bath" benefits from that mineral or in the potassium not tasting as salty as the sodium or in using recycled crushed glass filtration media with adhesion and cationic properties for finer filtration, but when they wander off into magnesium hydroxide flocculation/coagulation or claiming "the MagnaPool Hydroxinateur generates non-synthetic chlorine as a natural by-product of hydroxination, a process that mimics the production of non-synthetic chlorine that occurs within our own bodies to fight bacteria and disease", then this crosses the line into deceptive advertising. The process in the body that produces hypochlorous acid is a redox reaction where polymorphonuclear neutrophils (PMN) produce oxygen radicals that combine with abundant chloride ions. It's not even the same exact process as the electrolysis in Magnapool (though the resulting hypochlorous acid is the same) and the Magnapool electrolysis is identical to that of regular SWG systems since it only has to do with chloride levels and is independent of whether sodium, potassium or magnesium is used.

Another thing I don't like about Magnapool is that it is a complete system of electrolytic chlorine generator, recycled crushed glass filtration media and filter, and pump. A system isn't a bad thing, but for one touting environmental friendliness it should use a variable speed/flow pump or at least a 2-speed pump given the price of the system. That would save on electrical energy usage.

[EDIT]

I've been having a conversation on another forum (for pool industry professionals where I am an exception) about MagnaPool so have more information about it. Basically the following are the main points, though I'll update this as I find out more:

Poolrite (parent of MagnaPool) has many filed as well as lapsed patents. The Australian patent that is certified is 2009101121 which appears to be the same as U.S. patent application 20100270173. Note that this is older and there are newer applications especially about the filtration system (they do not use AFM from Dryden-Aqua in spite of that reference in the patent application I just linked to). These newer applications will not be publicly available until certified (or until filed in the U.S.).

1) The Hydroxinateur is a saltwater chlorine generator. Forget all the nonsense about non-synthetic chlorine.

2) Magnesium Hydroxide is likely produced from the high pH at the hydrogen gas generation plate and some of this is visible streaming out from returns as small particles seen at night. These apparently dissolve in the bulk pool water as expected and likely start to dissolve before then when the acidic water from the chlorine generation plate mixes to have a net pH probably under 8.0. There is still the claim of micro-flocculation, but I find this very suspect since the magnesium hydroxide should completely dissolve as it is not saturated and the bulk water is clear. There is a claim of zero turbidity measured via a Palintest turbidimeter (possibly the Micro 950 that has a range down to 0.01 NTU and a lowest standard of 0.02 NTU). It may be that it is the magnesium ion itself that has some coagulating capability being divalent (like calcium) and at higher concentration as described in their patent.

3) Magnesium and its health benefits are not disputed and I won't get into how much is absorbed through the skin, etc. as one can read about this elsewhere.

4) It seems that the primary salt is potassium chloride so the magnesium content is presumably low enough to not cause serious concern for salt splash-out, though this is not definite. It is true that pool waste water will be far less likely to cause "salt burn" because the sodium level is much lower. With dilution, the water should be able to be used for watering even sensitive plants whereas with a traditional saltwater chlorine generator pool much more dilution would be needed.

5) The filter uses a patent-pending glass filtration media that allows a flocculant /coagulant bed to form in the base of the filter (perhaps they meant at the top since I would expect this to be upon entry to the filter, but maybe not). They do something to prevent blocking the filtration bed too quickly -- something that spreads out capturing of material throughout more of the filtration media (though as described here this may be a common attribute of crushed glass media). This lets one go longer between backwashing. The filter also removes phosphates (again, proprietary) without the use of any additives. The result is very fine filtration (zero turbidity as noted above) with claimed lower chlorine demand compared to standard systems (presumably sand filters).

6) Having more of the filter media capture particles so longer time between backwashing means less water waste.

7) They say they can offer a variable speed pump (I noted that at least a 2-speed is required in some areas).

I don't dispute their lower chlorine demand, but I think a lot of it is stopping nascent algae growth via the phosphate and possibly algae spore removal since many pools are not properly maintained with a sufficient FC/CYA ratio. That would be consistent with what we see with residential pools time and time again from stabilized chlorine users with high CYA and with saltwater chlorine generator uses with too low an FC/CYA ratio. They are insisting that the removal of fine particles is the main reason for the lowered chlorine demand so this is in dispute. However, this is inconsistent with what we see with residential pools where there aren't differences in chlorine demand as a function of filter type and most chlorine demand is from loss from sunlight where overnight chlorine losses are relatively low.

There are still some inconsistencies such as claiming to not have to backwash as frequently but also claiming a lowering of THMs and chlorine demand from finer filtration. Unless what is caught in the filter is somehow isolated from being exposed to chlorine, the chlorine demand and THM production will continue from chlorine oxidation of substances caught in the filter. Backwashing would fix this, of course, but that means a more normal backwashing schedule. Perhaps what is meant is that the finer particles are initially caught and removed and from that point forward the level is lower so long as not too many fine particles are introduced into the pool over time.

If it wasn't for some of the marketing wording on how it works on their website, I'd feel much better about this product. It's too bad that NSF doesn't have a range of filtration tests to check for specific turbidity. As it stands right now, they have two standards -- one for sand and cartridge and another for DE. Hopefully this product will get certified under the existing DE standard that it should be able to pass (though there is a time limit for how quickly it must clear a pool with a specific turbidity load).

It will be interesting to compare the clarity of the water to both DE and adjunct systems such as Fiber Clear. Some similar filtration claims are made by that product in terms of fine filtration and its benefits (Fiber Clear claims removal of most algal spores and of phosphates, though I'm trying to find out how phosphate removal is done). I plan on getting some Fiber Clear and testing the turbidity in my pool before and after use this spring (along with continuing some THM tests I started at the end of last season).

[END-EDIT]

[waterbear]

I find it telling that DryfusDr has only made one post as a representative for the company but has filed 3 moderator reports threatening litigation if all negative references to Magnapool are not removed from the forum yet refuses to answer any of them in the public forum. I also find it telling that the one post he did make in answer to PoolGuyNJ was not in reference to any of the claims or criticisms of the system but only to say that he had no data on potassium chloride and soft stone and could not provide more than conjecture that magnesium chlorine is likely to be less problematic because it is hydoscopic and to use a sealer on the stone.