RO Water TDS

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jbritt

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I've been brewing for a while and have recently started learning about water chemistry and making adjustments. I never did before because I lived in western ny and the water was decent. Now living in Phoenix I quickly realized the water is terrible and really had no choice.

I have water softener and RO system with recently replaced filters. I also recently got TDS meter and RO water reads 25.1 tds. Tap water reads 800+ (varies) so maybe user error/meter error but if not thats pretty impressive for ro system.

So assuming the reading is accurate my question is the reading low enough to assume 100% ro water in water chemistry software? I don't have time to get a water report at the moment because I need to brew asap. If not low enough could I assume chemistry breakout of tds reading from local water report?
 
I think 25 tds output from 800+ source water is hella impressive!

I use Bru'n Water water tool which provides a place to enter source water parameters. It has some "canned" parameter sets including one for RO water that can be modified to suit actual user values. My RO system consistently provides 11 tds output from our ~250 tds well, and I used a Ward's test result from the latter to create proportional values to fill in my source water parameter set. I think you could do the same if your local water report has enough info for it.

Cheers!
 
So assuming the reading is accurate my question is the reading low enough to assume 100% ro water in water chemistry software?

I would. Any amount you are incorrect is going to be an amount you'd never taste the difference.

It could be interesting to have an analysis done on it but I wouldn't be too worried. A quick TDS check each brew will ensure things stay constant.
 
My RO system consistently provides 11 tds output from our ~250 tds well, and I used a Ward's test result from the latter to create proportional values to fill in my source water parameter set.

Not that it matters one bit at 11 ppm, but from a theoretical perspective, I wonder if it would be proportional. I suspect it would not, because the salts being removed are of different sizes. But I am not an expert in RO membrane theory/tech.
 
Right, it's 11 ppm, so even if I'm wrong, close enough for home brewing :)

Or commercial brewing. I know quite a few pros who pay less attention to their water than many of us on the forum.
 
I've been brewing for a while and have recently started learning about water chemistry and making adjustments. I never did before because I lived in western ny and the water was decent. Now living in Phoenix I quickly realized the water is terrible and really had no choice.

I have water softener and RO system with recently replaced filters. I also recently got TDS meter and RO water reads 25.1 tds. Tap water reads 800+ (varies) so maybe user error/meter error but if not thats pretty impressive for ro system.

So assuming the reading is accurate my question is the reading low enough to assume 100% ro water in water chemistry software? I don't have time to get a water report at the moment because I need to brew asap. If not low enough could I assume chemistry breakout of tds reading from local water report?
Have you ever thought of hooking the the RO system up prior to hitting the softener. You may be able to get a lower tds. The bigger molecules that get pulled out by the softener like calcium and magnesium will get trapped in your ro filter anyway but you won’t have the salts added and then have to be pulled out by the ro system as salts are smaller molecules.

By no means am I saying 25 tds is a lot lol but I genuinely believe you’ll have a lower tds by having the ro system before it goes into the softener.

But to answer your direct questions, 25 is low and I wouldn’t be concerned, that said on dark beers I would just air on the side of caution with the na and cl and just think about the 25 when adjusting
 
I’m no water expert but there used to be some systems on the market putting out 0 or close to 0 and the experts here trashed them as being unnecessary.
 
You're probably remembering "RODI" systems which add a deionization (ion exchange) stage after the membrane to push the TDS down to zero. Definitely not necessary.

As for where to connect a RO system given an existing softener: always after the softener, as that provides the greatest membrane performance and lifespan...

Cheers!
 
I have a small RO system from Buckeye Hydro , I’m on well water after my water softener and get 1-2 tds. I add 10 grams gypsum, 10 grams calcium chloride and 6 grams kosher salt, as a general rule to all my brews. I’m from WNY , living in the southern tier near Salamanca and Jamestown. Where were you before the move?
 
Since you don't have time on your first brew to get a water report I would do what Gordon Strong does with his RO recipes. He adjusts 5 gal of brewing liquor at a time to a pH of 5.5 with an acid. You can add your seasonings after the report on the next ones.
 
Not that it matters one bit at 11 ppm, but from a theoretical perspective, I wonder if it would be proportional. I suspect it would not, because the salts being removed are of different sizes. But I am not an expert in RO membrane theory/tech.
you are correct. Rejection of different ions varies.
 
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Since you don't have time on your first brew to get a water report I would do what Gordon Strong does with his RO recipes. He adjusts 5 gal of brewing liquor at a time to a pH of 5.5 with an acid. You can add your seasonings after the report on the next ones.

Does he really do that? Adjusting 5 gallons of good RO (or distilled) water to a pH of 5.5 would take only about 0.005 ml of 88% lactic acid (just try measuing that out!), because distilled/RO water has essentially no buffering capacity. The resulting 5.5 pH acidified water would be so weak (in buffering capacity) that the mash pH would end up being essentially whatever the Distilled Water pH of the malt(s) would have been. For most grists, this is going to result in a mash pH that's too high. I'd be pretty surprised if this is actually what Gordon does. But if he does, I don't see the point in it.
 
I’m in the Phoenix valley. My RO water ends up 11-25 TDS depending on how bad the tap water is that day. I always add minerals as if it were 0 TDS and go from there. Seems to of worked out for me so far. BTW - using RO water for your star san makes it clear.
 
Does he really do that? Adjusting 5 gallons of good RO (or distilled) water to a pH of 5.5 would take only about 0.005 ml of 88% lactic acid (just try measuing that out!), because distilled/RO water has essentially no buffering capacity. The resulting 5.5 pH acidified water would be so weak (in buffering capacity) that the mash pH would end up being essentially whatever the Distilled Water pH of the malt(s) would have been. For most grists, this is going to result in a mash pH that's too high. I'd be pretty surprised if this is actually what Gordon does. But if he does, I don't see the point in it.
Gordon is an avowed Luddite and he isn't interested in doing it in a better way. The only thing you can say for his method is that its better than nothing.

The problem that I see with other brewers adopting Gordon's approach is that they may overlook the nuance that he always starts with RO water. If a brewer starts with a typical tap water and adjusts to 5.5, the outcome could be far worse.

For some darker beer styles, Gordon's method could be fine. But for pale beers, it almost certainly won't produce a good result. The wort pH into the kettle is certain to be too high and the resulting beer is likely to be 'dull'.

Another thing to consider is that brewers should NOT infer that Gordon is a great BEER brewer from him winning Ninkasi awards. He actually won those awards via his Mead and Cider entries and by spending a sh*t ton of money and effort in entering dozens of beers, meads, and ciders. I can't say that he's a great BEER brewer, but I'll concur that he has an impeccable palate and is very skilled at amending and blending beers, meads, and ciders to produce end products that can win medals. Most of the rest of us brew and enter what we can make in a single shot. Great brewers can make that single shot count.
 
Gordon is an avowed Luddite and he isn't interested in doing it in a better way. The only thing you can say for his method is that its better than nothing.

The problem that I see with other brewers adopting Gordon's approach is that they may overlook the nuance that he always starts with RO water. If a brewer starts with a typical tap water and adjusts to 5.5, the outcome could be far worse.

For some darker beer styles, Gordon's method could be fine. But for pale beers, it almost certainly won't produce a good result. The wort pH into the kettle is certain to be too high and the resulting beer is likely to be 'dull'.

Another thing to consider is that brewers should NOT infer that Gordon is a great BEER brewer from him winning Ninkasi awards. He actually won those awards via his Mead and Cider entries and by spending a sh*t ton of money and effort in entering dozens of beers, meads, and ciders. I can't say that he's a great BEER brewer, but I'll concur that he has an impeccable palate and is very skilled at amending and blending beers, meads, and ciders to produce end products that can win medals. Most of the rest of us brew and enter what we can make in a single shot. Great brewers can make that single shot count.
I feel that Gordon is great at recreating a receipe based on a classic beer that he has had. I brewed his replication of U Flek Czeck Dark Larger that I received a 48 from a National beer judge at a local competition. The only deviation I did was a kettle mash instead of a decoction.
 
He adjusts 5 gal of brewing liquor at a time to a pH of 5.5 with an acid.
Details matter (see below).

88% lactic acid (just try measuing that out!)
FWIW, on p 11 of Modern Homebrew Recipes:
"I [Strong] adjust my RO water with 10% phospheric acid ...​
"I [Strong] use the more dilute acid since it is easier to measure ...".​

that they may overlook the nuance that he always starts with RO water
From my reading / studying of his two books (and the related HomeBrewCon presentations), RO water is one of a number of nuances in his brewing process that often get overlooked in home brewing forum discussion.

Maybe it's best for the home brewing community to view these books as classics (in the past) that many never actually read and move forward. Equations that model water (pH, etc) during the brewing process have come a long ways since 2013.
 
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FWIW, on p 11 of Modern Homebrew Recipes:
"I [Strong] adjust my RO water with 10% phospheric acid ...​
"I [Strong] use the more dilute acid since it is easier to measure ...".​

So, easier to measure with phosphoric than lactic, but still pointless if all he's doing is acidifying RO water to 5.5 and not adding any salts (to reduce mash pH) to the mash. Which is why I asked @hottpeper13 if that's really what Gordon is doing.

Equations that model water (pH, etc) during the brewing process have come a long ways since 2013.

They have certainly improved. But even in 2013, anyone paying attention to mash pH wouldn't have been acidifying RO water to 5.5 and calling it a day. EZWater and some others were around and none of them would have led a user to do that. Even the old Palmer sheet could more often than not get you in the ballpark.
 
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if all he's doing is acidifying RO water to 5.5 and not adding any salts
If you have read the books, you know the answer.

eta: I didn't see your addition ("They have certainly improved."). I'll repeat a comment

Maybe it's best for the home brewing community to view these books as classics (in the past) that many never actually read and move forward

and move forward.

:bigmug:
 
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If you have read the books, you know the answer.

I haven't read them, or at least I've never read a book that advocated that. Which, again, is why I asked if that's what he's really doing. Perhaps you could enlighten us.
 
If you have read the books, you know the answer.
I haven't read them,
While a couple of the specific techniques didn't "stand the test of time", the thought process (in the books) for understanding and enhancing a brewing process may still be worth the time it takes to read (and understand) the content.

Although, honestly, it may be that the simplest thing possible is for

[...] the home brewing community to view these books as classics [...] and move forward

:bigmug:
 
Although, honestly, it may be that the simplest thing possible is for [...] the home brewing community to view these books as classics [...] and move forward

Yes, you keep saying that. But I want to figure out more precisely what this supposed process is/was, as my read of @hottpeper13's post seems to be that it's something current. If you don't want to participate, fine, but feel free to stop playing gate keeper and telling me to move forward.

I imagine @hottpeper13 will be back sooner or later to clarify.
 
But I want to figure out more precisely what this supposed process is/was, as my read of @hottpeper13's post seems to be that it's something current
A fair and accurate summary of Strong's process (from his two books) is probably 3 to 5 printed pages, a long list of detailed footnotes, and a couple of technical review cycles.

Which is why I suggest reading the books - as one can get the information directly from the source [in 2013/2016].

#18 (above) has a lot of "food for thought" for those looking to brew with those 2013/2016 techniques in the mid-2020s.

but feel free to stop playing gate keeper and telling me to move forward.
Not telling anyone specifically, just suggesting that the community (as a whole) move forward.

:bigmug:
 
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A fair and accurate summary of Strong's process (from his two books) is probably 3 to 5 printed pages, a long list of detailed footnotes, and a couple of technical review cycles.

Which is why I suggest reading the books - as one can get the information directly from the source [in 2013/2016].

#18 (above) has a lot of "food for thought" for those looking to brew with those 2013/2016 techniques in the mid-2020s.

:bigmug:

I get that you don't want to talk about the details. Great. But I'm not going to read the books just to clarify what @hottpepper13 meant about Gordon's RO water acidification, if in fact he is even quoting the books you are talking about. So for the love of God, stop advising me right now.
 
Does he really do that? Adjusting 5 gallons of good RO (or distilled) water to a pH of 5.5 would take only about 0.005 ml of 88% lactic acid (just try measuing that out!), because distilled/RO water has essentially no buffering capacity. The resulting 5.5 pH acidified water would be so weak (in buffering capacity) that the mash pH would end up being essentially whatever the Distilled Water pH of the malt(s) would have been. For most grists, this is going to result in a mash pH that's too high. I'd be pretty surprised if this is actually what Gordon does. But if he does, I don't see the point in it.
I strongly agree. I tried Gordon's method several years ago when I decided to start monkeying around with RO--everyone else is doing it, right? Trying to hit pH 5.5 with RO left me spitting nails. It was like boxing a Bobo doll. Fortunately, I'm lucky enough to have some quite passable tap water, so I've never tried it again.
 
Another thing to consider is that brewers should NOT infer that Gordon is a great BEER brewer from him winning Ninkasi awards. He actually won those awards via his Mead and Cider entries and by spending a sh*t ton of money and effort in entering dozens of beers, meads, and ciders. I can't say that he's a great BEER brewer, but I'll concur that he has an impeccable palate and is very skilled at amending and blending beers, meads, and ciders to produce end products that can win medals. Most of the rest of us brew and enter what we can make in a single shot. Great brewers can make that single shot count.
Savage!
 
Test Boom GIF
 
I strongly agree. I tried Gordon's method several years ago when I decided to start monkeying around with RO--everyone else is doing it, right? Trying to hit pH 5.5 with RO left me spitting nails. It was like boxing a Bobo doll. Fortunately, I'm lucky enough to have some quite passable tap water, so I've never tried it again.

The whole folly (i.e. pointlessness) of acidifying RO to 5.5 pH aside...

It's not hard to calculate the amount of acid needed to do it. And it's a very small amount. Measuring the ph of the acidified water, OTOH, would be nigh on impossible with a standard pH meter. There are not enough ions for the probe to effectively engage with. I think a boxing a Bobo doll is a pretty good analogy.
 
The whole folly (i.e. pointlessness) of acidifying RO to 5.5 pH aside...

It's not hard to calculate the amount of acid needed to do it. And it's a very small amount. Measuring the ph of the acidified water, OTOH, would be nigh on impossible with a standard pH meter. There are not enough ions for the probe to effectively engage with. I think a boxing a Bobo doll is a pretty good analogy.
Ah ha! Thanks for clearing that up!

It's been a long time since I tried it, but it was such a rotten experience that I remember it quite well. As you suggest, the calculations were easy enough, it was getting the confirmation of my results that was the issue. I ended up seesawing all over the place. It is an absolutely stupid way to make brewing water. Without question, it was one of the most infuriating Friday nights I've ever spent in my brewery and I'll never do it again.

Edit made after VikeMan's like of my post: Going back to your initial remark, "Does he really do that?," has me wondering if he simply does his math and then assumes good starting conditions will inevitably yield good beer in the keg? Having comprehensively squandered the first ten years of this hobby learning that this isn't the case, I've spent the last twenty years wrestling with the corollaries of that observation. Your pH needs to be monitored and adjusted from mash to KO...even into the keg, depending upon the strain. Likewise, your salts also require adjustment from mash to kettle via iteration--would be nice if we could monitor them, too. It's a big pain in the butt and it requires a lot of data points, scrupulous notes, and patience, patience, patience. But it does work.

Brewing would be a lot easier if there really were silver bullets, though.
 
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Going back to your initial remark, "Does he really do that?," has me wondering if he simply does his math and then assumes good starting conditions will inevitably yield good beer in the keg?

Really just speculating here until I learn what he really does (or did, if it's something from 2013 (or whenever) that he no longer does), but if it's "acidify RO water to 5.5 ph, mash with that water, no other additions, and call it a day," that would typically not be good starting conditions. OTOH, if it's something like "acidifidy RO water to 5.5 pH, then add salts in amounts needed reach a target mash pH for the particular grist," that could be a good starting point. But the thing about the latter scenario is that the original acidification to 5.5 pH (with the tiny amount of acid and no significant buffering capacity) wouldn't make a measurable difference in the mash PH, i.e. the salts alone would have given the same result.

Your pH needs to be monitored and adjusted from mash to KO...even into the keg, depending upon the strain. Likewise, your salts also require adjustment from mash to kettle via iteration--would be nice if we could monitor them, too. It's a big pain in the butt and it requires a lot of data points, scrupulous notes, and patience, patience, patience. But it does work.

Measurement is a good thing. Case in point... flabby IPAs. As the amount of (dry) hops used in (American) IPAs began to approach ludicrous levels, very few brewers paid attention to the impact on final pH, which tended to increase. Some brewers discovered that adding a little acid after fermentation would "brighten up" the flavor without realizing why. Even more discovered that targeting a lower mash pH (i.e. the lower end of a "normal" mash pH range or even a little lower) would do the same thing, without really thinking about why.

Most of the top IPA (NEIPA) brewers are pretty tight lipped about their process, but I suspect they are paying attention to pH at packaging time.
 
Wow, you guys are incredible! # 1 Gordon's books read like a conversation and I enjoy reading them. He uses 1/4 tps per 5 gal and then adds the CaCl2 or CaSO4 depending on the style. I was only trying to help the OP on his first brew until he got his report.

I have not a clue as to what Gordon does now. I can't use his water profile because his measurements are in tps not grams. I weigh out my salts and use acidulated malt for pH control. My SOP's are not his SOP's so I just use the grain and hop bill along with the mash protocol for the recipes. I also don't agree on steeping the crystal and black malts separately, mostly because I can use 1/2 filtered house water for raising the pH.
 
Wow, you guys are incredible! # 1 Gordon's books read like a conversation and I enjoy reading them. He uses 1/4 tps per 5 gal and then adds the CaCl2 or CaSO4 depending on the style. I was only trying to help the OP on his first brew until he got his report.

I have not a clue as to what Gordon does now. I can't use his water profile because his measurements are in tps not grams. I weigh out my salts and use acidulated malt for pH control. My SOP's are not his SOP's so I just use the grain and hop bill along with the mash protocol for the recipes. I also don't agree on steeping the crystal and black malts separately, mostly because I can use 1/2 filtered house water for raising the pH.

Thanks for the clarification. Interestingly, 1/4 tsp of 10% phosphoric acid would take 5 gallons of RO water well below 5.5 pH (but still weakly buffered). Only 0.056 ml would be needed (for 5.5). So I wonder why he thought he was hitting 5.5 pH. But even 1/4 teaspoon of 10% phosphoric acid won't move the pH needle much (if at all) in a typical mash. The addition of CaCl2 or CaSO4 would "save" a lot of beers from a mash pH perspective.

From post #13 I thought maybe Gordon (via you) was recommending acidifying RO down to 5.5 and not adding salts. Hopefully @jbritt will not do that.
 
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from Modern Homebrew Recipes, p.23:

"Determine water salts - I prefer the taste of low mineral additions, so for most beers I simply add 1 tsp of calcium salts (calcium chloride or calcium sulfate) per 5 to 6.6 gallon (19 to 25L) to get about 50 ppm of calcium.
Prepare brewing liquor - On most batches, I add about 1/4 tsp of 10% phosphoric acid per 5 gallons of RO water to achieve a pH of 5.5 at room temperature."

Just for the hell of it, I opened up Bru'nWater and selected the default RO water profile, plugged in 0.31 g each of CaCl2 and CaSO4 to get to 49 ppm and 1 mL of 10% phosphoric acid. Predicted pH is 5.34 for my Imperial IPA grain bill and 5.02 4.97 for my Black IPA grain bill.

edit - corrected predicted pH value
 
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"Determine water salts - I prefer the taste of low mineral additions, so for most beers I simply add 1 tsp of calcium salts (calcium chloride or calcium sulfate) per 5 to 6.6 gallon (19 to 25L) to get about 50 ppm of calcium.
Prepare brewing liquor - On most batches, I add about 1/4 tsp of 10% phosphoric acid per 5 gallons of RO water to achieve a pH of 5.5 at room temperature."

Hmm. That could be read a couple of ways:

1) Add 1/4 tsp of 10% phosphoric acid to 5 gallons of RO to get the water to 5.5 pH. (It's not the right amount to do that, but it could have been the intent, however misguided.)

-or-

2) A tsp of calcium salts plus 1/4 tsp of 10% phosphoric acid to get the mash pH to 5.5. (This would make more sense, although the correct amounts would be grist dependent, and that small amount of acid isn't doing much.)

Just for the hell of it, I opened up Bru'nWater and selected the default RO water profile, plugged in 0.31 g each of CaCl2 and CaSO4 to get to 49 ppm and 1 mL of 10% phosphoric acid. Predicted pH is 5.34 for my Imperial IPA grain bill and 5.02 for my Black IPA grain bill.

What pH predictions do you get if you delete the phosphoric acid?
 
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