RO Water and the downsides?

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Gizzygone

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I’m considering ordering a RO Buddie system from amazon... the relatively low cost seems to make sense vs buying distilled water and building a profile.

I’m curious, though, since when you research you don’t seem to get any reputable answers (only marketing-heavy opinions of RO vs Distilled...): is there any downside to RO water?

One thing that keeps coming up is bacteria or bio-film in the lines... I know the boil will take care of that, but I’d likely use the system for Coffee and other uses around the house where it may not be boiled fully.

I’m curious what you all think?
 
One downside is it can take a long time to collect enough water for the mash if you have a cheap home RO system, so you have to plan ahead.

I've been investigating them since right now I'm just running to the Glacier Water machine down the street and filling a 5gal plastic carboy every time I brew. That's the downside for me, right now. :D
 
You will be better off using distilled water and building your water with that. It is dirt cheap and there is no upkeep. That is what I do. The cost of that system will buy years of distilled water not to mention all of the waste water an RO system generates.
 
cubalz said:
You will be better off using distilled water and building your water with that. It is dirt cheap and there is no upkeep. That is what I do. The cost of that system will buy years of distilled water not to mention all of the waste water an RO system generates.
Click to expand...

The math works out very simply if you brew more than occasionally. An average 5 gallon batch is going to require at least 8 gallons of brewing water. With a cheap RO rig you'll be even within 8-10 batches. Not to mention if you use the same RO system for drinking water, you'll be even in a matter of weeks.

The only downsides are:
1. Takes time to make it. These system only make a trickle. Easily overcome with planning.
2. It does strip the alkalinity from the water. This is usually a GOOD thing, but it's hard to add back without adding a lot of sodium.
3. It is a maintenance item. The pre-filters need to be replaced occasionally, and the membrane will need to be replaced every few years.
 
It depends on the input water.

If the filters are changed and the system is flushed (auto or manual) on a regular basis, there shouldn't be any bacteria or bio-film build up.

If the input water is laden with iron or sulfur bacteria (that causes a slimy buildup) they should be mostly filtered out in the pre-filter (1-5 micron) as well as the carbon filter. This of course adds to the maintenance expense of the unit. Sulfur bacteria are smaller (1 micron) than iron bacteria (3-5 micron) and may make it through the pre-filter.

Any other bacteria and you probably shouldn't be using that water for drinking purposes.
 
A properly maintained R.O. system with reasonable input water should get you close enough to distilled water for the purpose of building profiles. (At least according to A.J. in the Brewing Water Chemistry Primer thread)

I have an under-counter R.O. system that I use for Drinking, Ice, and Cooking. But I still get my brewing water from the "Water Store" (R.O. w/ U.V. sanitizing). It's just easier for me that way. And at $0.25/Gallon, it's cheap enough.
 
cubalz said:
You will be better off using distilled water and building your water with that. It is dirt cheap and there is no upkeep. That is what I do. The cost of that system will buy years of distilled water not to mention all of the waste water an RO system generates.
Click to expand...

Ummmm....not really. It may depend on what you pay for distilled water, and how easily or difficult it is to get it. As for me, I needed over $6 of store-bought water to meet my needs for a batch.

When I put in an RO system, that cost went away. I bought that RO system for $135 after about my 7th batch. I just finished my 52nd batch using RO water from that system. If you do the math, you'll see that I'm way ahead of buying storebought water, plus--PLUS--it's right there for me to use when I need it. No store trips, no gas, no miles put on the car, no lugging it.

Now, maybe you're where distilled water is dirt cheap, and you don't care about lugging it home. But please don't tell people that it's way expensive for what you get, because it's not.
 
Gizzygone said:
I’m considering ordering a RO Buddie system from amazon... the relatively low cost seems to make sense vs buying distilled water and building a profile.

I’m curious, though, since when you research you don’t seem to get any reputable answers (only marketing-heavy opinions of RO vs Distilled...): is there any downside to RO water?

One thing that keeps coming up is bacteria or bio-film in the lines... I know the boil will take care of that, but I’d likely use the system for Coffee and other uses around the house where it may not be boiled fully.

I’m curious what you all think?
Click to expand...


I've used an RO system since...early 2016. There is no practical difference between distilled and RO water.

I flush the system for 30 seconds before and after use, and haven't had any issues in the 45 batches of water I've produced with it. Typically that will be around 10 gallons as I also use it for my Keurig at work, and for other brewing-related uses like sterilizing my aeration wand in boiling water.

I just take a gallon of that RO water to work, and it will greatly reduce the need to clean out scale from the coffeemaker, as there is virtually no mineral load in the water (6 ppm TDS).

*****************

It's not hard to set one of these up, provided you have a faucet spout you can attach a garden-hose adapter to. Below is a pic showing my original system; the blue line connects to the faucet spout, the white line is output and goes into an aquatainer, and the yellow line is discharge.

The filter housing hangs on a piece of plywood on the wall. It's in my garage and I wanted some way to take it in the house if temps were too cold. You could easily do something similar by attaching it to a stand, and then put away in a closet when you're done.

******************

If there's a downside, it's that you don't produce RO water fast. There are different throughput volumes. Mine is 50 gallons per day, but that is only under ideal circumstances. Depends on water temp (cold is less efficient) and pressure. You can get filters rated at higher throughput. They cost more, but not that much more, and I wish I had the 100gpd filter. May buy that one.

My answer to that problem is the aquatainer. I widened the vent hole to 1/4" with a normal drill bit, and the supply tube fits snugly into it. Crack the other lid to allow for air to escape, and off it goes.

I dump that 7 gallons of water in my kettle--if I don't need that much, I fill some gallon jugs I have--and then set it to filling from the RO filters. It's the first thing I do when brewing so that by the end of brew day, I'm all set for the next one.

rosystem.jpg
 
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That RO Buddie system is a bunch of garbage. Steer clear of it and get an RO system from a reputable place.
 
If you do a little reading up on the RO systems you'll find that it's basically just a kit of commodity components. The tubing and fittings are standard, the housings are standard, the pre-filters are generic. The only component that makes a real functional difference is the membrane. Get a name brand Filmtec membrane from a reliable source - i bought mine on Amazon and i'm pretty sure its counterfeit. Although even the counterfeit does a good enough job for making brewing water.

This is a good DIY project to assemble yourself if you are even a little bit handy.

The other comment i have is that the 5 and 6 stage systems are a waste of money for making brewing water. 2-3 pre-filters and the membrane is all you need. You don't even need a tank.
 
Distilled is a buck a gallon here.
My typical 11 gallon batch uses a little over 16 gallons to brew plus 4 more gallons to keep my hex covered during recirculation.
So, $20 in water per batch.
I brew almost 200 gallons each year. That'd be close to $400 gallons of distilled water each year.
That would be epically stupid.

I bought an APEC ROES-50 for $199 a couple of years ago. It produces 20 gallons in 8 hours.
If you can't figure the math, it paid for itself 4X in that time and is still going strong.

I will add that I recently added a booster pump to get that production level, as the ROES-50 is spec'd at 90 psi input pressure and my well pump can be anywhere between 35 and 55 psi. I worked with Russ @Buckeye_Hydro to put a pump kit together for their model 6800 pump and it's been singing nicely ever since.

Big fan of Russ and Buckeye Hydro, good stuff at decent prices plus a hella lot of wisdom to draw from...

Cheers!
 
The only disadvantage I have found with RO has been on the one or two occasions where I realize the night before brewing that I have forgotten to collect the RO water over the last few days that it takes to collect enough for the large batches I was doing from the home improvement store sized (under sink) systems. As #12 exemplifies it is possible to put together a 60 GPD system at quite reasonable cost. That post also points out that you can, knowing the price of local RO or DI water, figure out how long it will take to recover the cost of the system given the rate at which you brew.

Or you can take the approach advocated in #11: buy a skid, an atmospheric tank, a pressure tank, some pumps, float switches and relays and put together a system plumbed (plastic pipe) into your brewery with enough water always in the pressure tank to support any brew you do any time you want to do it. I did this and had a lot of fun with the project. As many of my projects do this one got a little out of hand (http://www.pbase.com/agamid/image/124857348) but there are other benefits to having an RO system. When the well pump fails on Boxing day (as it did once) there was plenty of water for drinking, cooking and flushing toilets while repairs (took several days) were underway.

With respect to bacterial contamination: Membranes are shipped wet with hydrogen peroxide (I think it is) and are thus sterile but the rest of the system isn't necessarily sterile but this doesn't seem to be a problem. I seem to recall that the under-sink systems want you to flush them before use. Perhaps the peroxide from the membrane is, even diluted in 3 gal of water (or whatever the pressure tanks hold) sufficient to sterilize the tanks and lines. What really mystifies me is that the water in the atmospheric tank in my system stays clean apparently forever. Yes, it's air vent is covered with a fine screen to keep bugs out and inverted to keep dust out but I would think, given the tenacity of life, that something would use the CO2 as a carbon source and start to grow in there. But that doesn't seem to be the case. I have never tried plating any of this water onto media to see whether anything would grow but it always looks, smells and tastes clean and there is no biofouling of the tank itself or plumbing.
 
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Here’s another question: I’m thinking a portable unit would suit me best:

Hook it up to a hose bib, and let it flow into a 6gallon fermentation bucket with a spigot. (My wife won’t allow me to drill a hole in our new granite countertops!)

What separates, say, the $50 RO Buddie on Amazon from a $200 APEC unit?
 
Assuming that you're adding minerals as appropriate for the style brewed, the main thing that you'll want to understand and account for is that the zinc has been stripped from the water. Adding a supplement that has the proper amount of zinc, is desirable. The Wyeast yeast nutrient has zinc in it.

While my recommendation is valid, I've frequently forgotten to add the yeast nutrient to batches and they still seem to finish well. So apparently, its not critical.
 
I never add nutrient to the wort but I always add it to the starter. I've thus never done a side by side with and without zinc so all I can say is that this aspect of the use of RO does not appear to be harmful but then I can't say adding some to the wort might not make the beer even better. I guess the other observation that might be pertinent here is that my ferments are always vigorous.
 
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On my next brew i'm going to start using the wyeast nutrient to get the recommended zinc. I've never had a major fermentation issue, but I am on the hunt for something....
 
Gizzygone said:
[...]What separates, say, the $50 RO Buddie on Amazon from a $200 APEC unit?
Click to expand...

Just going by the ads the APEC is a five stage unit with two carbon block filters, a third "taste and odor" post-membrane carbon filter, includes a pressure tank and faucet, and uses much larger filters than the RO Buddie, which is a three-stage system sans tank and faucet...

Cheers!
 
The sediment and carbon filters on the 'RO buddie' are undersized for the application, and the carbon filter won't remove the chlorine/chloramine due to lack of surface area, which will still allow chlorine through and will ultimately damage the membrane.
 
Another reason to consider DIY is that you can tailor the filters to your source water. For example if you have well water you likely need to be more concerned with sediment and not at all worried about chlorine or chloramine.

Standard 10” filter housings are the way to go. The filters are extremely common and can be had cheap.
 
Rough outline....

1. Determine requirements - What is your source water like? Do you have a lot of particulate, is there chlorine or chloramine, is the water extremely hard? Very important to consider how much water you need and how fast you want to make it. What is your source water pressure and temperature? Does it vary over the year? Do you want to use this system for the rest of your house too? May need to consider tanks and other hardware such as pumps in addition to brewing. Where are you going to install it. Need a water source and a drain. Also if you want to use it for something like an ice maker you need to consider the pressure drop of the tubing normally used. If you have a long run sometimes you can have issues where there isn't enough pressure to push through the line and thus you need a bigger tube.

2. Choose components - Choose number of pre-filters and types based on your water. At a minimum you'll want a sediment filter and a carbon block filter. If you have high particulate water you may want 2 stages of sediment filters before the carbon filters. If you have chloramine its generally suggested to get a carbon block filter optimized for that. In almost all cases the standard 10" filter size is what you want. If you have unusually high volume requirements or need to fit in a really tight space this might lead to a different decision. Choose the appropriate membrane based on your desired flow rate. Get matching flow restrictor for the brine water. If you have post-filtering requirements select those filters and appropriate housings. Count up the size and types of fittings you need. Generally these systems are put together with push connectors and plastic pex tubing. These are very cheap, simple and flexible. You could go overkill and hard pipe everything but its not necessary.

3. Build - this is like putting together a lego kit for the most part. Put the housings in the main bracket. Attach inlet and outlet fittings. Cut tubing to length and connection stages.

4. Test and fix leaks

5. Install in final location if permanent installation.
 
Thanks for that info! I did some looking for filters and there is a whole range of microns so this will help. I have city water and it is super hard and has a high amount of iron in it. This will be mostly for brewing so I'm not super concerned about how many gallons per day.

I'm going to do some more research and I'll post back what I ended up doing. Thanks again for the info.
 
I bought mine from Bulk Reef Supply. Buckeye Hydro is another good place. Start there if you are serious about an RO system.

I use about 9-10 gallons per brew which takes a few hours to gather the water. I usually collect the day before. I brew about every three weeks and usually use the RO system every week to gather water for drinking, coffee or tea.

It beats lugging 10 gallons from Wally World and in the long run will save money.

Living down in the swamp, every year we have the chance of being hit with a hurricane. If one does hit again, like Katrina several years ago where the stores were without water for 1+ week, I know I will always have a water to make drinking water. so that was another plus for me.
 
Transamguy77 said:
I have city water and it is super hard and has a high amount of iron in it.
Click to expand...
Then it needs to be softened before it goes to your RO system. If you are operating at high recovery rates (say 50% to make the math easy) you have to appreciate that the concentration of calcium and bicarbonate are going to be twice in the conentrate what they were in the feed water. Close to the membrane they will be higher still and precipitation of calcium carbonate, which will clog the membrane, is likely. Systems that run at low pressure typically have such low recovery (by design) that this is not such a serious problem.
 
ajdelange said:
Then it needs to be softened before it goes to your RO system. If you are operating at high recovery rates (say 50% to make the math easy) you have to appreciate that the concentration of calcium and bicarbonate are going to be twice in the conentrate what they were in the feed water. Close to the membrane they will be higher still and precipitation of calcium carbonate, which will clog the membrane, is likely. Systems that run at low pressure typically have such low recovery (by design) that this is not such a serious problem.
Click to expand...
Well how long will it take to clog the membrane? I'm not interested in purchasing a softener system also, is it necessary?
 
Hi guys - I just read through this thread for the first time. There are a fair number of misconceptions, misunderstandings, and only "kinda-correct" info in this thread re RO systems. We're happy to talk with anyone considering a system.

Russ
513-312-2343
 
Transamguy77 said:
Well how long will it take to clog the membrane? I'm not interested in purchasing a softener system also, is it necessary?
Click to expand...

Here's the low-down: In general, the more expensive the replacement membranes are, the more it makes sense to pretreat as appropriate (e.g., soften) the water sent to an RO system. On commercial RO systems where replacement RO membranes can be hundreds of $ or more, and where use is heavy, softening the feedwater is commonplace. On residential-scale systems (typically 150 gpd or less) that use 1812 membranes (1.8" in diameter and 12" long, nominal), replacements are relatively inexpensive (~$30 to $55), and people are much less likely to soften the feedwater due to the initial expense and required upkeep/maintenance of the softener (primarily adding salt pellets).

But - one other thing to consider - if your water is hard, you may want to consider the whole-house benefits of a softener. Not only will your RO membranes last longer, but you'll be able to reduce the amount of water sent to drain by your RO, you'll reduce the amount of soap and detergent you use, and you'll protect your other plumbing fixtures (hot water heater, faucets, etc.) as well.

Brewers often have a knee-jerk aversion to softeners because they've heard softened water will be higher in sodium. But that sodium issue is more than adequately address by the RO process.

Russ
 
I'm not a huge advocate of ion-exchange softening, but it is useful in some cases. One area that softening is especially useful for, is your home's hot water system. Feeding softened water to just the water heater can significantly improve the heater's life and performance. My house had the entire internal water system hooked to the water softener, but I replumbed it to feed only the hot water heater. I'm glad I did.

By the way, I feed my RO from the softened water circuit.
 
That's good to know ^
I have been contemplating getting a R/O system, as I have been going to the grocery store to get my R/O water from the Glacier machine.

John
 
mabrungard said:
I'm not a huge advocate of ion-exchange softening, but it is useful in some cases. One area that softening is especially useful for, is your home's hot water system. Feeding softened water to just the water heater can significantly improve the heater's life and performance. My house had the entire internal water system hooked to the water softener, but I replumbed it to feed only the hot water heater. I'm glad I did.

By the way, I feed my RO from the softened water circuit.
Click to expand...

Last year we had to replace our water heater, which had been fed only softened water for its entire service life.

Know when it was installed? 1992. I think a 25-year service life is a reasonable testament to the value of using softened water in a water heater. :)

We have softened water feeding all faucets in our house except for the cold water kitchen faucet. That's where I draw my brewing water which is then cut w/ RO.
 
Buckeye_Hydro said:
Hi guys - I just read through this thread for the first time. There are a fair number of misconceptions, misunderstandings, and only "kinda-correct" info in this thread re RO systems. We're happy to talk with anyone considering a system.
Click to expand...

I know this is you main line of business, but I'm always up to learning more. If I've given out incorrect info please let me know. Maybe consider putting together a FAQ for RO systems?
 
Transamguy77 said:
Well how long will it take to clog the membrane? I'm not interested in purchasing a softener system also, is it necessary?
Click to expand...
That depends on how hard and alkaline the water is and the design recovery rate. The answer you want, of course, is 'it takes forever' and it does as long as the concentration of the 'limiting salt' (which in most cases is going to be calcium carbonate) in the concentrate is less than the saturation level under the operating parameters of the system and the nature of the water. The cheap under the sink units solve this problem by operating at very low recovery. The installation instructions will usually tell you what the maximum hardness of the water that is fed to these units should be. I think its about 17 grains per gallon. That's 17*17.1 = 290 ppm as CaCO3. That's more hardness than most people encounter and that's really the temporary hardness limitation. Permanent hardness does not result in clogging (unless calcium sulfate becomes the limiting salt but I think that would be pretty unusual). I guess I should note that my recollection that the undersink units can handle up to 17 gpg is a bit suspect given that the conversion to ppm is 17.1 but I really do think the number is around that. Thus most brewers can simply buy one of these units and sail on with little fear of having a clog or simply replacing a membrane cartridge (which isn't that expensive for these small systems) as necessary.

But whatever it is that makes us want to home brew makes many of us want to tinker and some home brewers are also tree huggers and appalled that every gallon of water that goes into their mash tun sends 4 down the drain. Some assuage their guilt by saving this water for laundry or watering their lawns (but a real tree hugger doesn't water his lawn, does he). And some put pumps in front of their membranes and restricting valves after thus increasing recovery, wasting less water, getting more permeate faster and increasing the chance of clogging. One can, of course, simply keep changing out membranes as the alternatives are to accept lower recovery or feed the thing with softened water. If your water is wicked hard as you suggest it is likely that you would have a whole house softener anyway as really hard water is a big PITA WRT boilers, laundry, dishwasher and hot water heater.

An under the sink unit is what it is but if you buy anything else a good dealer will ask you for a water analysis and let you know if there is a potential problem. If you want to kluge something yourself you are on your own. The limiting salt calculations are not difficult and I can post them if you want me to.
 
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mabrungard said:
I'm not a huge advocate of ion-exchange softening,
Click to expand...
This suggests that you prefer an alternative but the rest of the post suggests that you simply are not a huge advocate of softening by any means. Could you clarify and in particular, if you are saying you prefer an alternative method, tell us what it is?

mabrungard said:
One area that softening is especially useful for, is your home's hot water system. Feeding softened water to just the water heater can significantly improve the heater's life and performance. My house had the entire internal water system hooked to the water softener, but I replumbed it to feed only the hot water heater. I'm glad I did.
Click to expand...


I've done pretty much the same thing. I just took the softener out in the house. When I replaced the boiler based heating system with a water to water heat pump I also tossed the hot water heater in favor of an instantaneous hot water heater which provides the DHW and backs up the heat pump if it fails or it just gets to cold for it. The 'Combi - Boiler' is as sensitive to hardness as any other type but when the exchanger efficiency drops you get an error message (sent to your smart phone, of course) and you then just circulate some vinegar to remove the lime deposit. Tip: monitor the pH of the recirculating vinegar. It will rise as long as it is removing CaCO3. When there is no more CaCO3 to dissolve the pH stops rising and you are finished.

mabrungard said:
By the way, I feed my RO from the softened water circuit.
Click to expand...
In the brewery there is a ion exchange softener but it feeds only the RO system and the boiler.

So I guess I too would have to say that I am not a big fan of softeners in general. But the calcium part of my temporary hardness is not high enough (around a mEq/L) to be a problem for the laundry etc. The Combi has gone a year without a problem But the brewery boiler and RO unit get softened water and the heat pump exchanger loops, both ground and air handler, are filled with RO plus glycol and corrosion inhibitors. The contractors thought I was nuts but then a lot of people do.[/QUOTE]
 

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