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Old 03-26-2014, 02:54 PM   #1
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Water quality

There's a good thread running on 12VDC watermakers. So as not to hijack that thread, I'll pose a related question. Given that most folks recognize the luxury of making their own water while underway, what precautions are folks taking to ensure the biological quality of self-made water?

City water used to fill a water tank is typically safe to drink as it comes out of the tap. It has passed through multiple filtration systems, and is also typically routinely tested and chlorinated. That doesn't mean you can automatically trust dock water at a marina, although most of us do. That doesn't mean it stays safe in our water tanks, although many expect it to.

A watermaker will desalinate water to a drinkable level. Raw water filters for sediment and (less often) oil are typically used to preserve the membrane's health. However, no reverse osmosis water maker will remove the bacteria in the raw water being used to create fresh water. The bugs are just too small and will pass un-molested into your water tank.

My doctor went high-order on me last spring, and insisted I install a water sterilizer on the output from my fresh water tank. She immediately grasped the concept of making water, and listened carefully to my standard operating procedure of only making water when I was reasonably sure it was "clean". She then reminded me that one cannot assess the degree of "cleanness" of water by simply looking at it, smelling it, or tasting it! MAKE SURE THE WATER IS STERILIZED before you drink it, she yelled. OK, OK, I get it. I put in a 40W 110VAC sterilizer, and trust that it works!

By way of example, the City of Victoria, BC (population 78K as of 2006) was ordered to treat their raw sewage in 2006. They have yet to do so, and the projected date for their sewage treatment plant is 2018. This is an example of how tough it is to tell if the raw water you are using to make water aboard your boat is safe. Would you make water in the vicinity of Victoria, knowing they discharge their raw sewage (yeah, that's UNTREATED, RAW sewage) directly into the Straits of Juan De Fuca? Nope, not me. Ditto as I pass by the many small shoreside communities, marinas, fishing lodges, etc. in WA state, BC and Alaska.

I guess the overall point of this post is to suggest there's more to the water making issue than simply voltage, current, DC vs AC, gal per hour, etc. One cannot always make water when you need it! And, given the difficulty in actually measuring "consumability" of water, it can't be done with a salinity meter. Having said that, I have a watermaker aboard. I use it regularly. I use it judiciously, in what (I hope) is good water. And I sterilize it immediately prior to consumption. So far, so good. YMMV.

Regards,

Pete
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Old 03-26-2014, 03:12 PM   #2
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Originally Posted by jungpeter View Post
There's a good thread running on 12VDC watermakers. So as not to hijack that thread, I'll pose a related question. Given that most folks recognize the luxury of making their own water while underway, what precautions are folks taking to ensure the biological quality of self-made water?

City water used to fill a water tank is typically safe to drink as it comes out of the tap. It has passed through multiple filtration systems, and is also typically routinely tested and chlorinated. That doesn't mean you can automatically trust dock water at a marina, although most of us do. That doesn't mean it stays safe in our water tanks, although many expect it to.

A watermaker will desalinate water to a drinkable level. Raw water filters for sediment and (less often) oil are typically used to preserve the membrane's health. However, no reverse osmosis water maker will remove the bacteria in the raw water being used to create fresh water. The bugs are just too small and will pass un-molested into your water tank.

My doctor went high-order on me last spring, and insisted I install a water sterilizer on the output from my fresh water tank. She immediately grasped the concept of making water, and listened carefully to my standard operating procedure of only making water when I was reasonably sure it was "clean". She then reminded me that one cannot assess the degree of "cleanness" of water by simply looking at it, smelling it, or tasting it! MAKE SURE THE WATER IS STERILIZED before you drink it, she yelled. OK, OK, I get it. I put in a 40W 110VAC sterilizer, and trust that it works!

By way of example, the City of Victoria, BC (population 78K as of 2006) was ordered to treat their raw sewage in 2006. They have yet to do so, and the projected date for their sewage treatment plant is 2018. This is an example of how tough it is to tell if the raw water you are using to make water aboard your boat is safe. Would you make water in the vicinity of Victoria, knowing they discharge their raw sewage (yeah, that's UNTREATED, RAW sewage) directly into the Straits of Juan De Fuca? Nope, not me. Ditto as I pass by the many small shoreside communities, marinas, fishing lodges, etc. in WA state, BC and Alaska.

I guess the overall point of this post is to suggest there's more to the water making issue than simply voltage, current, DC vs AC, gal per hour, etc. One cannot always make water when you need it! And, given the difficulty in actually measuring "consumability" of water, it can't be done with a salinity meter. Having said that, I have a watermaker aboard. I use it regularly. I use it judiciously, in what (I hope) is good water. And I sterilize it immediately prior to consumption. So far, so good. YMMV.

Regards,

Pete
Our watermakers, as do many, offer and recommend accessories including a UV sterilizer. In fact these are the accessories recommended: Fresh Water Flush, pH Neutralizer, Commercial Pre-Filter, Oil Water Separator, U.V. Sterilizer.

Even so, we only drink bottled water, whether on the boat or home. Yes, living on the coast, our water at home leaves much to be desired as well. We drink lots of water and it's our primary beverage so it's worth it to us. Even so, the sterilizer is important even for shower water and other use. Bacteria can easily settle in your shower head.
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Old 03-26-2014, 03:14 PM   #3
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Pete: I would assume that your "water sterilizer" is of the ultraviolet type. Those do an excellent job, if matched to your water output flow rate, on most water born bacteria. There are reasons that they are not commonly used in public water systems. One of those is that they treat at only one point in the distribution system. The water may continue to carry bacteria if the pipes, fixtures, etc.. have bacteria present. I would suggest that the entire system on any boat be chlorinated at 50ppm (parts per million or 50mg/l) at least once a year, then completely flushed through every fixture. Chlorine needs "contact time" so hold in tank for a minimum of 12 hours prior to flushing.

On a similar note- everything in our environment will eventually be carried in our waters. Bacteria is only a part of the problem that can contaminate water. VOC's, SOC's, and the ones I would be most concerned about in foreign water sources at dock or not are nitrites and nitrates (usually related to agricultural means and methods). Some may be filtered, some treated with additional chemicals like the chlorine and some the best method is simply aeration.
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Old 03-26-2014, 03:37 PM   #4
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....However, no reverse osmosis water maker will remove the bacteria in the raw water being used to create fresh water. The bugs are just too small and will pass un-molested into your water tank...
We lived on RO water for over 10 years, with no UV and never got sick from the water. Some people may blamed RO water when it may be poor storage practices. RO systems take out more than 99% of bacteria and virus. Virus .02-.4 micron in size, bacteria .4-1 micron in size. An RO membrane has a pore size of .00001 microns.

There is nothing wrong with going the extra step with a UV sterilizer but the bugs are not to small.

This from the Centers for Disease Control and Prevention

Reverse Osmosis Systems
  • Reverse Osmosis Systems use a process that reverses the flow of water in a natural process of osmosis so that water passes from a more concentrated solution to a more dilute solution through a semi-permeable membrane. Pre- and post-filters are often incorporated along with the reverse osmosis membrane itself.
  • A reverse osmosis filter has a pore size of approximately 0.0001 micron.
  • Reverse Osmosis Systems have a very high effectiveness in removing protozoa (for example, Cryptosporidium, Giardia);
  • Reverse Osmosis Systems have a very high effectiveness in removing bacteria (for example, Campylobacter, Salmonella, Shigella, E. coli);
  • Reverse Osmosis Systems have a very high effectiveness in removing viruses (for example, Enteric, Hepatitis A, Norovirus, Rotavirus);
  • Reverse Osmosis Systems will remove common chemical contaminants (metal ions, aqueous salts), including sodium, chloride, copper, chromium, and lead; may reduce arsenic, fluoride, radium, sulfate, calcium, magnesium, potassium, nitrate, and phosphorous.
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Old 03-26-2014, 03:57 PM   #5
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Pete: I would assume that your "water sterilizer" is of the ultraviolet type. Those do an excellent job, if matched to your water output flow rate, on most water born bacteria. There are reasons that they are not commonly used in public water systems. One of those is that they treat at only one point in the distribution system. The water may continue to carry bacteria if the pipes, fixtures, etc.. have bacteria present. I would suggest that the entire system on any boat be chlorinated at 50ppm (parts per million or 50mg/l) at least once a year, then completely flushed through every fixture. Chlorine needs "contact time" so hold in tank for a minimum of 12 hours prior to flushing.

On a similar note- everything in our environment will eventually be carried in our waters. Bacteria is only a part of the problem that can contaminate water. VOC's, SOC's, and the ones I would be most concerned about in foreign water sources at dock or not are nitrites and nitrates (usually related to agricultural means and methods). Some may be filtered, some treated with additional chemicals like the chlorine and some the best method is simply aeration.
This does bring to mind one of the most dangerous storage containers of bacteria-hot tubs and jacuzzi's. Regular flushing is essential for them as the water that sits in the piping between uses is a breeding ground for bacteria. We do make sure ours is flushed very frequently.
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Old 03-26-2014, 04:11 PM   #6
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Very true on the hot tubs, my boat does not have one yet.
I would like to add since this is a water quality thread...that lead and copper are also major concerns in any water that may be used for consumption. I would think it fairly common to have copper water lines in many vessels and those nice looking polished brass fixtures are made with lead, copper and nickel with often an assortment of other heavy metals. The best indicator of whether those are leaching into or out of your tap is a simple PH test on the water. PH adjustments are easily made when refilling the tank from either your RO system or from the dock supply. You would be surprised at the PH range in drinking water. Water plant operators routinely adjust PH during the treatment process to enable a more effective treatment process for finished water and what may be a desired PH in one system may not be in another city's system depending on their source water. A low or high PH will result in the leaching of the lead and copper found in your lines and fixtures.
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Old 03-26-2014, 04:24 PM   #7
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I hate to hijack this post but one last item. I have been a licensed water operator in Ga. for over 25 years and treat and test water routinely. If I had to give only one recommendation on improving water quality I have found that a 50/50 solution of water with Makers Mark is best for all consumption of this fluid.
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Old 03-26-2014, 04:32 PM   #8
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I hate to hijack this post but one last item. I have been a licensed water operator in Ga. for over 25 years and treat and test water routinely. If I had to give only one recommendation on improving water quality I have found that a 50/50 solution of water with Makers Mark is best for all consumption of this fluid.
You would get a better percentage split if you cut that 50% water to just one ice cube.
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Old 03-26-2014, 04:41 PM   #9
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It seems the world is becoming paranoid over water quality and bacteria. Drink more bottled water says Coca Cola. (Great profit margin in selling water)

I'm OK with drinking water straight from the taps, whether it be at the dock or home. No filtration, sterilization, or other treatment is required on my boat as long as I keep my tanks clean.

Its quite simple, really. Put only clean water in. Only clean water comes out.
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Old 03-26-2014, 04:47 PM   #10
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It seems the world is becoming paranoid over water quality and bacteria. Drink more bottled water says Coca Cola. (Great profit margin in selling water)

I'm OK with drinking water straight from the taps, whether it be at the dock or home. No filtration, sterilization, or other treatment is required on my boat as long as I keep my tanks clean.

Its quite simple, really. Put only clean water in. Only clean water comes out.
....while a little thoughtful thinking and management of your system is in order...hardly the end of the world type scenario....

Like LarryM...been drinking the same old stuff for 60 years and never a stomach cramp...even all my travels through South & Central America and military survival schools.

I really believe what more and more studies are showing (and of course within reason and no immune system issues)...the cleaner you live the sicker you are.....
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Old 03-26-2014, 06:29 PM   #11
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Like Larry M and Psneeld I too have been drinking "watermaker water" for many years with no ill-effects whatsoever.

It may well get a bad reputation because of its purity. Unlike city water, it contains no chlorine or other stuff that might kill the sluggy buggies, so they tend to thrive. Keeping your pumps, pipes and tanks clean is essential.

Two things that most watermaker newbies notice:
1. It is almost tasteless and not refreshing to drink - Ulysses has the remedy for that!
2. It makes huge amounts of soap suds - use less shampoo.
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Old 03-26-2014, 07:07 PM   #12
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It seems the world is becoming paranoid over water quality and bacteria. Drink more bottled water says Coca Cola. (Great profit margin in selling water)

I'm OK with drinking water straight from the taps, whether it be at the dock or home. No filtration, sterilization, or other treatment is required on my boat as long as I keep my tanks clean.

Its quite simple, really. Put only clean water in. Only clean water comes out.
AMEN!!

I firmly believe the problem is that we (as in humans) are sanitizing ourselves to death. Too much hand sanitizer, too much chlorine in our water, etc. Our bodies can and will adjust to ingestions of various beasties in nature with little to no ill effect. Of course, sometimes Montezuma comes a'calling, but overall I believe my premise holds true.
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Old 03-27-2014, 06:17 AM   #13
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Folks that invest in a UV system might consider how easy it is to use a valve or two on the tank fill system and clean dockside water as its taken on , and then clean the tank output as its used onboard.

For folks that travel with only city water a rapid dump system is worth installing if replacing a tank.

A 2 inch valve to allow the tank to empty into the bilge will only freshen most bilges.

Towns vary in water quality , so when the FW tank is full of what tastes and smells like the municipal swimming pool , and you get to a better source , a dump and refill is worth the effort.

City water can be killed by clear sections of hose in the water system that is exposed to day light.
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Old 03-27-2014, 07:09 AM   #14
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I think your concept of RO water is all wrong. RO water is probably the purest water you will encounter anywhere on the planet short of distilled water. Bacteria and viruses do not pass through. Now that doesn't mean your tank and pipes are clean, but it has nothing to do with RO water.

I think much of the fuss about water quality, at least in the US, is just like the fuss over fuel additives. Its easy to scare people into thinking there is something bad in their water or diesel and that they should buy your product, and conveniently impossible to prove that their product does nothing useful at all. Now I'm not saying that a UV sterilizer doesn't sterilize, just that there needs to be something in the water to sterilize for it to be useful and worth buying.
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Old 03-27-2014, 10:59 AM   #15
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I think your concept of RO water is all wrong. RO water is probably the purest water you will encounter anywhere on the planet short of distilled water. Bacteria and viruses do not pass through. Now that doesn't mean your tank and pipes are clean, but it has nothing to do with RO water.

I think much of the fuss about water quality, at least in the US, is just like the fuss over fuel additives. Its easy to scare people into thinking there is something bad in their water or diesel and that they should buy your product, and conveniently impossible to prove that their product does nothing useful at all. Now I'm not saying that a UV sterilizer doesn't sterilize, just that there needs to be something in the water to sterilize for it to be useful and worth buying.
Spot on!

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Old 03-28-2014, 04:41 AM   #16
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Currently looking for a 12 volt uv sterilizer that can handle a single faucet for drinking water. Found many 110/220 volt systems but would like to avoid using the inverter. Found some systems which come with additional filters, but none that are just the UV sterilizer. 2 gallons or 7 liters a minute would be fine.

Background, while we use our water maker regularly we do fill up from the municipal supply when we are at the dock. This year we know of three boaters here in St. Lucia who have acquired some parasite from the municipal water.
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Old 03-28-2014, 10:55 AM   #17
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This year we know of three boaters here in St. Lucia who have acquired some parasite from the municipal water.
One of the problems with any water, including the "municipal water" is that from the time it leaves the city water station until the time we drink it there are many possibilities of contamination. I personally trust my watermaker more than 50% of the marinas I've visited. Much of the piping to the docks is questionable. I've seen docks piped off of lines that were originally put in for irrigation. You have deterioration of the pipes and of the hoses. Then you have your tanks and lines on the boat to add to the picture. Now to add to that, there are many municipalities that have had water samples fail in various bacteria count as well.

We can talk about what we've done safely for decades but that doesn't mean it's always safe today. I'd also caution that as one ages the risk increases. Plus the water we are getting today may not be the water we drank safely all those years. We have a more contaminated environment.

Last, one final reason we drink bottled water. Taste. You travel along the coast and you find some towns with really awful tasting (and even smelling) water. Water from your watermaker likely doesn't taste as well as you wish. One talks about cost but then most people drink lots of soda and/or coffee and/or tea or other beverages such as beer or wine or liquor. Bottled water in the volume we buy it is less expensive than the majority of the other drinks. Drinking bottled helps encourage us to drink it. Yes, we both average about five bottles a day (or more) if using the 16 oz bottles. Others with us drink a lot too. But let's say I drink four bottles of water a day, that costs me about $0.50. That's less than the cost of a couple of soft drinks. Less than the cost of one beer. Actually less than the cost of four cups of coffee. Plus extremely convenient as we can easily carry plastic bottles to any deck, to the tender, to the park, wherever. And when we pay for bottled water out somewhere, such as a restaurant, it's no more than anything anyone else at the table is drinking.

We choose to drink bottled water. Yes, we have UV and PH check and all the other bells and whistles with our watermaker. But that's for all the other uses we make of water. For drinking, our personal choice is to stick with the bottles. We do respect those of you who choose to do otherwise, but we're not going to change.
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Old 03-28-2014, 11:06 AM   #18
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[QUOTE=Bay Pelican;223114]Currently looking for a 12 volt uv sterilizer that can handle a single faucet for drinking water. ... 2 gallons or 7 liters a minute would be fine...[QUOTE]

PURA Addon-3 15530100 3 GPM Ultraviolet UV Water System - FreshWaterSystems.com
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Old 03-28-2014, 01:40 PM   #19
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I think your concept of RO water is all wrong. RO water is probably the purest water you will encounter anywhere on the planet short of distilled water. Bacteria and viruses do not pass through. Now that doesn't mean your tank and pipes are clean, but it has nothing to do with RO water.

I think much of the fuss about water quality, at least in the US, is just like the fuss over fuel additives. Its easy to scare people into thinking there is something bad in their water or diesel and that they should buy your product, and conveniently impossible to prove that their product does nothing useful at all. Now I'm not saying that a UV sterilizer doesn't sterilize, just that there needs to be something in the water to sterilize for it to be useful and worth buying.
"...RO water is probably the purest water you will encounter anywhere on the planet". That's a pretty broad statement, given the vagaries of typical installation, maintenance, and use of RO aboard recreational vessels.

"...Bacterial and viruses do not pass through". Really? Guess I'll have to defer to differing opinions voiced by Internists and Oncologists working at the Seattle Cancer Care Alliance, a medical institution founded by Nobel laureates in the field of blood disorders instead. There's a real good reason intakes to RO systems are never properly placed downstream from head or holding tank discharges, nor operated in suspect environments.

I'm reminded of the old story of the guy walking down the street in Miami on a hot summer day carrying a folded umbrella:

Onlooker: Why in the world are you carrying a folded umbrella in Miami in the summer?
Guy: That's not an umbrella. It's an elephant protector.
Onlooker: Huh? There isn't an elephant within 1000 miles of Miami!
Guy: Works good, huh.

In a sense, post-water tank sterilization of water aboard is a bit like an elephant protector, or any other form of insurance. However, as one who has been stepped on by the elephant in this regard (you really don't want to contract a blood infection. Trust me on this), I'll continue to pay for, and use sterilization downstream from my water tank, no matter the source of the water that goes into my tank. The few hundred bucks it costs pales in comparison to the downside.

And I'm gratified that this thread has resulted in some meaningful dialog. Only good things come from such discussions.

Regards,

Pete
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Old 03-28-2014, 02:17 PM   #20
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Based on my research...you get more germs from touching door knobs, touching money and licking you fingers after a chicken dinner than from RO water.......

http://www.labdepotinc.com/articles/pure-water-information.html

Reverse Osmosis

Reverse osmosis is the most economical method of removing up to 99% of your feed water's contaminants.
To understand reverse osmosis we must first understand osmosis. During natural osmosis, water flows from a less concentrated solution through a semipermeable membrane to a more concentrated solution until concentration and pressure on both sides of the membrane are equal.
In water purification systems, external pressure is applied to the more concentrated (feed water) side of the membrane to reverse the natural osmotic flow. This forces the feed water through the semipermeable membrane. The impurities are deposited on the membrane surface and sent to drain and the water that passes through the membrane as product water is, for the most part, free of impurities.
A reverse osmosis membrane has a thin microporous surface that rejects impurities, but allows water to pass through. The membrane rejects bacteria, pyrogens, and 90-95% of inorganic solids. Polyvalent ions are rejected easier than monovalent ions. Organic solids with a molecular weight greater than 200 Daltons are rejected by the membrane, but dissolved gases are not as effectively removed.
Reverse osmosis is a percent rejection technology. The purity of the product water depends on the purity of the feed water. The product is typically 95-99% higher in purity than that of the feed water.
Due to the restrictive nature of the membrane, the flow rate is much slower than other purification technologies. This slow flow rate means that all RO systems require a storage tank to provide a constant supply of RO water ready when you need it
- See more at: What is Pure Water?

From the Center For Disease Control....

CDC - A Guide to Drinking Water Treatment Technologies for Household Use - Camping, Hiking, Travel - Drinking Water - Healthy Water
Reverse Osmosis Systems


  • Reverse Osmosis Systems use a process that reverses the flow of water in a natural process of osmosis so that water passes from a more concentrated solution to a more dilute solution through a semi-permeable membrane. Pre- and post-filters are often incorporated along with the reverse osmosis membrane itself.
  • A reverse osmosis filter has a pore size of approximately 0.0001 micron.
  • Reverse Osmosis Systems have a very high effectiveness in removing protozoa (for example, Cryptosporidium, Giardia);
  • Reverse Osmosis Systems have a very high effectiveness in removing bacteria (for example, Campylobacter, Salmonella, Shigella, E. coli);
  • Reverse Osmosis Systems have a very high effectiveness in removing viruses (for example, Enteric, Hepatitis A, Norovirus, Rotavirus);
  • Reverse Osmosis Systems will remove common chemical contaminants (metal ions, aqueous salts), including sodium, chloride, copper, chromium, and lead; may reduce arsenic, fluoride, radium, sulfate, calcium, magnesium, potassium, nitrate, and phosphorous.
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