Is RODI water safe to drink?

[WVNed]

I drank some. It dissolved my teeth.

 

[Greg P]

Our's is mountain water. Our treatment plant was upgraded in 2010 and they claimed then that we had the best water in the world.
Tap water here is blue in the bathtub and in white buckets.
The city uses chlorine and I don't bother filtering my drinking water, I just let a jug sit open in the fridge.

 

[madweazl]

Been drinking it for about seven years now, still kickin... I'm a retired Marine, I drank it for years while I was serving and in large quantities. I still drink 1/2-2/3 gpd.

 

[robbyg]

Did you read it? Do you agree with it? All of it? If not, then you too, god forbid, might disagree with the author.

Apparently is is unsafe to drink water with tds less than 100 ppm. Omg, everyone on the east coast of the US is about to die! Certainly everyone in Boston is doomed from excessively clean tap water.

Seriously, that is just utter nonsense. most people in the US do not rely on their drinking water for calcium and magnesium. If that were a real issue, the EPA would require it in tap water and bottled water. No such requirement exists.

sure, you could drink too much di water, or just really clean tap water, and you might have issues. Drinking too much of anything may cause issues of various sorts. That doesn’t make it unsafe. People should always have a varied diet, including beverages.

Do you and your family drink RODI water?

 

[madweazl]

Do you and your family drink RODI water?

I bring a gallon of RODI water with me every single day, for at least seven years. No issues yet but I'm only 44, maybe it will catch up with me...

 

[Paleozoic_reefer]

It may be safe to drink I guess but for the amount of water (and money) I waste just to get a single gallon of the stuff I would rather put it in my tank rather than the toilet!

 

[madweazl]

It may be safe to drink I guess but for the amount of water (and money) I waste just to get a single gallon of the stuff I would rather put it in my tank rather than the toilet!

Run the waste water outside to the garden or lawn. I havent setup tanks at this house but we did at our last place. Now that I'm using a lot more water (two tanks), I'll be investing in a 1:1 system over the inefficient BRS system that I currently have.

 

[Paleozoic_reefer]

Run the waste water outside to the garden or lawn. I havent setup tanks at this house but we did at our last place. Now that I'm using a lot more water (two tanks), I'll be investing in a 1:1 system over the inefficient BRS system that I currently have.

@madweazl definitely run my waste line to my garden so it's not a total loss; but still feel guilty considering water in the Southwest where I live is a pretty scarce and a limited commodity...

 

[MombasaLionfish]

The dangers of dihydrogen monoxide

Facts About Dihydrogen Monoxide

Dihydrogen Monoxide Research Division provides an international clearinghouse for information on Dihydrogen Monoxide including current research results, governmental regulations, and exposure and contamination alerts. Dihydrogen Monoxide (DHMO) can be dangerous to humans. Dihydrogen Monoxide...

www.dhmo.org

 

[MombasaLionfish]

When the water is sterilized it removes pretty much everything from the water including all it minerals and ions. Water is a polar molecule which means it has a slight positive and negative charge on either side due to the way the electrons are being shared so it likes to dissolve other polar or ionized molecules. When we mix this soft water (no minerals) with salt it becomes hard water again with a lot of minerals such as magnesium chloride sodium chloride etc.

 

[mattzang]

i used RODI to make some cold brew a few times, didn't seem to taste much different and wasn't worth the effort

i also haven't died yet so that's a plus

 

[Hans-Werner]

RODI water is excellent for the preparation of tea or coffee and also your baby food will add necessary minerals and osmolytes. I think it is more healthy than a mineral water with a high concentration of chloride and/or sodium.

 

[Otrips]

I'm confused people here actually saying that If you took 2 properly sanitized containers. Filled on with tap water another with RO/DI water and sealed them. The one containing the RO/DI water is more likely to contain harmful bacteria and support the growth of that bacteria? That defies all logic.
The entire point of RO/DI systems is to remove (some/most) bacteria, viruses from the water, along with other contaminates, chemicals, metals and organics. Sure there will be less chlorine and such to sanitize the water, but there will also be fewer organics to feed the bacteria, not to mention less bacteria in the water to start with. The only exception I see might be if the water is stored in an unsanitary environment.

I'd love to see one of the lab techs here put this to a test in a controlled environment.
1, RO/DO water in sealed & sterilized container.
2, Tap water in a sealed & sterilized container.
3, RO/DO water in an open container.
4, Tap water in an open container.
5, RO/DO water refrigerated.
6, Tap water refrigerated.
Test for bacterial grown after a reasonable amount of time. A week or so would be the most I'd imagine people let water sit around for.
Test again after a longer period of time to allow for further culture of the bacteria.
And if possible type it, to determine if any strains that may be found are actually harmful.


Heck lets take this further. If RO/DI water for some reason actually encourages the growth of bacteria and whatnot why do we store so much of it for our tanks? Wouldn't we just be culturing bacteria? Should we stop storing RO/DO water & only store tap water instead? What about the other contaminates? I guess RO/DI is good in that aspect. I suppose in that case we should stop storing water all together. One could say that when we add it to our tanks the salt helps kill off that bacteria. Should we immediately make salt water with RO/DI? But doesn't it go bad? Should we store our water with only highly pure salt and add all the necessary elements immedialy before using? But then again Salt only kills certain strains. Could many of the problems we see in our tanks actually be caused by storing RO/DI water? Would more water changes help, but then again how do we store all that water?
Something to think about...

Personally I'll continue drinking, washing my hands and showering with tap water. Using RO in my coffee & Tea, for some reason it just tastes so much better. And when flushing/changing the coolant in my vehicles. I'll leave the RO/DI for the fishes.

 

[Randy Holmes-Farley]

Do you and your family drink RODI water?

I’ve said several times in this thread that I advise against it, mostly due to concerns about bacteria. It also does not taste good.

 

[Randy Holmes-Farley]

I'm confused people here actually saying that If you took 2 properly sanitized containers. Filled on with tap water another with RO/DI water and sealed them. The one containing the RO/DI water is more likely to contain harmful bacteria and support the growth of that bacteria? That defies all logic.
The entire point of RO/DI systems is to remove (some/most) bacteria, viruses from the water, along with other contaminates, chemicals, metals and organics. Sure there will be less chlorine and such to sanitize the water, but there will also be fewer organics to feed the bacteria, not to mention less bacteria in the water to start with. The only exception I see might be if the water is stored in an unsanitary environment.

I'd love to see one of the lab techs here put this to a test in a controlled environment.
1, RO/DO water in sealed & sterilized container.
2, Tap water in a sealed & sterilized container.
3, RO/DO water in an open container.
4, Tap water in an open container.
5, RO/DO water refrigerated.
6, Tap water refrigerated.
Test for bacterial grown after a reasonable amount of time. A week or so would be the most I'd imagine people let water sit around for.
Test again after a longer period of time to allow for further culture of the bacteria.
And if possible type it, to determine if any strains that may be found are actually harmful.


Heck lets take this further. If RO/DI water for some reason actually encourages the growth of bacteria and whatnot why do we store so much of it for our tanks? Wouldn't we just be culturing bacteria? Should we stop storing RO/DO water & only store tap water instead? What about the other contaminates? I guess RO/DI is good in that aspect. I suppose in that case we should stop storing water all together. One could say that when we add it to our tanks the salt helps kill off that bacteria. Should we immediately make salt water with RO/DI? But doesn't it go bad? Should we store our water with only highly pure salt and add all the necessary elements immedialy before using? But then again Salt only kills certain strains. Could many of the problems we see in our tanks actually be caused by storing RO/DI water? Would more water changes help, but then again how do we store all that water?
Something to think about...

Personally I'll continue drinking, washing my hands and showering with tap water. Using RO in my coffee & Tea, for some reason it just tastes so much better. And when flushing/changing the coolant in my vehicles. I'll leave the RO/DI for the fishes.

that isn’t what I said. Perhaps others did, but the concern is different.It has been demonstrated that bacteria grows on the downstream side of an ro membrane and can be released into the finished water. That is no concern at all for a reef tank that teams with bacteria. It is a concern for drinking. That is why it is strongly recommended by experts to keep ro drinking systems properly sanitized.

 

[Randy Holmes-Farley]

Here’s a study:

Assessment of the extent of bacterial growth in reverse osmosis system for improving drinking water quality - PubMed

This study was carried out to assess reverse osmosis (RO) treatment efficacy of drinking water in terms of biological stability in the distribution system. Two flat-sheet RO membranes were used in this study. Experiments were designed to investigate the growth of biofilm and bulk phase bacteria...

www.ncbi.nlm.nih.gov

In spite of the low nutrient contents and few cells in the RO permeates, monitoring of the model distribution systems receiving the RO permeates showed that remarkable biofilm accumulation and bulk cell growth occurred in the RO permeate water. In quasi-steady state, the total cell numbers in the biofilm and bulk water were of order 10(3) cells/cm(2) and 10(3) cells/mL, respectively,

and

Therefore, efforts to minimize bacterial growth in the RO permeate water and in the distribution system must consider post-disinfection.

 

[madweazl]

Here’s a study:

Assessment of the extent of bacterial growth in reverse osmosis system for improving drinking water quality - PubMed

This study was carried out to assess reverse osmosis (RO) treatment efficacy of drinking water in terms of biological stability in the distribution system. Two flat-sheet RO membranes were used in this study. Experiments were designed to investigate the growth of biofilm and bulk phase bacteria...

www.ncbi.nlm.nih.gov

In spite of the low nutrient contents and few cells in the RO permeates, monitoring of the model distribution systems receiving the RO permeates showed that remarkable biofilm accumulation and bulk cell growth occurred in the RO permeate water. In quasi-steady state, the total cell numbers in the biofilm and bulk water were of order 10(3) cells/cm(2) and 10(3) cells/mL, respectively,

and

Therefore, efforts to minimize bacterial growth in the RO permeate water and in the distribution system must consider post-disinfection.

Bet mine is pretty impressive; the RO membrane hasnt been replaced, opened, or cleaned since 2013 LOL.

 

[Otrips]

Here’s a study:

Assessment of the extent of bacterial growth in reverse osmosis system for improving drinking water quality - PubMed

This study was carried out to assess reverse osmosis (RO) treatment efficacy of drinking water in terms of biological stability in the distribution system. Two flat-sheet RO membranes were used in this study. Experiments were designed to investigate the growth of biofilm and bulk phase bacteria...

www.ncbi.nlm.nih.gov

In spite of the low nutrient contents and few cells in the RO permeates, monitoring of the model distribution systems receiving the RO permeates showed that remarkable biofilm accumulation and bulk cell growth occurred in the RO permeate water. In quasi-steady state, the total cell numbers in the biofilm and bulk water were of order 10(3) cells/cm(2) and 10(3) cells/mL, respectively,

and

Therefore, efforts to minimize bacterial growth in the RO permeate water and in the distribution system must consider post-disinfection.

I wasn't implying you said anything, just a general feeling I got from reading everyone comments and this entire thread at once.


Am I reading it wrong or isn't this suggesting that a lower number of cells grew compared to tap water, additionally a significant number of the cells were heterotrophic which use organic carbon as their food source, breaks down sludge and poses little if any health risks to humans as many are prolific on our own skin?

Wouldn't most be flushed out as it is more prolific in bulk water than the biofilm?

Activated carbon also significantly reduces heterotrophic bacteria, do you know if this study filtered the water through a carbon filter immediately prior to the RO membrane similar to how our RO systems do?

Doesn't an RO system filter out most harmful bacteria, protozoa and Viruses down to about 0.0001 micron leaving very little if any harmful bacteria able to make it based the final stage and able to grow in comparison to tap water?
Which makes me curious as to what all the other cell growth consisted of.
Obviously anything that could grow in such low nutrient environment would likely flourish due to the lack of sanitizers present such as chlorine at that stage. But again very little would make it that far, unless it was somehow introduced when changing filters. Which I suppose is a good reason to wash your hands prior. Much would also be flushed out before it could colonize to harmful levels with regular use. Another reason to flush the system a little before using and use it often.

Despite advancements in municipal water treatment facilities it's not always perfect as this study suggests by growing more bacteria in tap water than RO. It may also be safe to assume that living at the end of a line and/or attempts to conserve water in your own home may actually promote further bacterial growth as the water remains more stagnant.

In my view an RO system would only further purify the water making it safer wise than regular tap water if used the way most would use the system for drinking water. Not to mention all the other non-bacterial impurities an RO system removes. Luckily I live in an area with pretty darn good tap water and I'm not afraid to drink it despite the chlorine smell being overwhelming at times. However in many areas the water out of the tap may not be so great.

 

[Randy Holmes-Farley]

I wasn't implying you said anything, just a general feeling I got from reading everyone comments and this entire thread at once.


Am I reading it wrong or isn't this suggesting that a lower number of cells grew compared to tap water, additionally a significant number of the cells were heterotrophic which use organic carbon as their food source, breaks down sludge and poses little if any health risks to humans as many are prolific on our own skin?

Wouldn't most be flushed out as it is more prolific in bulk water than the biofilm?

Activated carbon also significantly reduces heterotrophic bacteria, do you know if this study filtered the water through a carbon filter immediately prior to the RO membrane similar to how our RO systems do?

Doesn't an RO system filter out most harmful bacteria, protozoa and Viruses down to about 0.0001 micron leaving very little if any harmful bacteria able to make it based the final stage and able to grow in comparison to tap water?
Which makes me curious as to what all the other cell growth consisted of.
Obviously anything that could grow in such low nutrient environment would likely flourish due to the lack of sanitizers present such as chlorine at that stage. But again very little would make it that far, unless it was somehow introduced when changing filters. Which I suppose is a good reason to wash your hands prior. Much would also be flushed out before it could colonize to harmful levels with regular use. Another reason to flush the system a little before using and use it often.

Despite advancements in municipal water treatment facilities it's not always perfect as this study suggests by growing more bacteria in tap water than RO. It may also be safe to assume that living at the end of a line and/or attempts to conserve water in your own home may actually promote further bacterial growth as the water remains more stagnant.

In my view an RO system would only further purify the water making it safer wise than regular tap water if used the way most would use the system for drinking water. Not to mention all the other non-bacterial impurities an RO system removes. Luckily I live in an area with pretty darn good tap water and I'm not afraid to drink it despite the chlorine smell being overwhelming at times. However in many areas the water out of the tap may not be so great.

Reverse osmosis prevents bacteria and viruses from getting through the membrane. It does not prevent them from growing on the other side unless you sanitize it.

I would not store tap water without disinfection either.

 

[Dkeller_nc]

I wasn't implying you said anything, just a general feeling I got from reading everyone comments and this entire thread at once.


Am I reading it wrong or isn't this suggesting that a lower number of cells grew compared to tap water, additionally a significant number of the cells were heterotrophic which use organic carbon as their food source, breaks down sludge and poses little if any health risks to humans as many are prolific on our own skin?

Wouldn't most be flushed out as it is more prolific in bulk water than the biofilm?

Activated carbon also significantly reduces heterotrophic bacteria, do you know if this study filtered the water through a carbon filter immediately prior to the RO membrane similar to how our RO systems do?

Doesn't an RO system filter out most harmful bacteria, protozoa and Viruses down to about 0.0001 micron leaving very little if any harmful bacteria able to make it based the final stage and able to grow in comparison to tap water?
Which makes me curious as to what all the other cell growth consisted of.
Obviously anything that could grow in such low nutrient environment would likely flourish due to the lack of sanitizers present such as chlorine at that stage. But again very little would make it that far, unless it was somehow introduced when changing filters. Which I suppose is a good reason to wash your hands prior. Much would also be flushed out before it could colonize to harmful levels with regular use. Another reason to flush the system a little before using and use it often.

Despite advancements in municipal water treatment facilities it's not always perfect as this study suggests by growing more bacteria in tap water than RO. It may also be safe to assume that living at the end of a line and/or attempts to conserve water in your own home may actually promote further bacterial growth as the water remains more stagnant.

In my view an RO system would only further purify the water making it safer wise than regular tap water if used the way most would use the system for drinking water. Not to mention all the other non-bacterial impurities an RO system removes. Luckily I live in an area with pretty darn good tap water and I'm not afraid to drink it despite the chlorine smell being overwhelming at times. However in many areas the water out of the tap may not be so great.

So there seems to bit of confusion here, and possibly as a result of me not going into sufficient explanation in my posts about water sterilization/sanitation.

As Randy noted, it turns out that bacteria can indeed grow in highly purified water if that water is stored in a manner that allows inoculation of bacteria and/or bacterial spores from the environment. This is despite the fact that the water when produced has virtually zero dissolved nutrients - either inorganic such as ammonia and/or nitrates, or organic in the form of dissolved organic compounds. There's a good bit of speculation in the scientific literature as to why this might be the case, and one logical explanation is that the water can adsorb very small amounts of nitrogenous compounds from the air.

However, note that isn't the same as saying that RODI water is better at bacterial growth promotion than tap or unpurified water. If you put highly purified water into a suitable container and sterilize it (with, for example, and autoclave), and the container is fully sealed, there will be zero bacteria in it - forever. Or at least until the container breaks down and loses its seal integrity.

The reason that tap water is safe to store for drinking purposes for at least a fairly short period of time at room temperature is because of the chlorine/chloramine content. Those sanitants will continue to kill and/or inhibit the growth of bacteria for multiple days. However, if you remove the chlorine/chloramine from the tap water with a carbon filter, it will grow bacteria quite well - often to the point of cloudiness after setting for several days at room temperature.

The above is the reason that RO/DI systems intended for drinking purposes have an filter on the end of the dispenser. In addition to providing a final filtration step, it also serves as a one-way valve that prevents airflow and its potential bacterial contamination from back-flowing into the system when the water flow is turned off. And when the system is setup, or is broken into to change filters, a sanitization chemical is used in the system to kill any bacteria that might've been introduced, and to remove any biofilms that may have grown in the system since it was last maintained.