RO water not exactly at 0 ppm

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Jayjay1976

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Hey Jayjay, my set up is fro tap to sediment filter, to carbon filter, to RO, to post active carbon filter, to deionization filter. Let me see if i can upload a pic of the set up, its almost like the HbrewO but just my take on it i guess.
@Buckeye_Hydro is definitely the expert here so I will defer to his opinion.

IMHO, I believe you can just take out the deionization element, it's simply not needed for brewing. If we were on a forum about maintaining reef tanks with hard corals and their extremely demanding water requirements it would be useful; for home brewing it is simply overkill. That being said if you are making adjustments to your water before brewing with mineral salts, the DI won't hurt and you can be assured in assuming your ions really are at 0-0-0-0 in your water calc. Just don't drink the water, only use it to brew.
 

deuc224

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Yeah im not planning on doing anything but brewing with this water and will be adding minerals back in. Really appreciate the feedback
 

day_trippr

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If you look closely I bet you'll find the input to the DI stage comes from a tee that joins the pressure tank to the RO stage output. All you should need to do is remove the tube between the tee and the DI stage, then unplug your product tube from the DI state output and plug it into the tee...

Cheers!
 

deuc224

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If there is no pressurized storage tank, there is absolutely no benefit, and I would say there is a detriment to having a carbon filter between the RO and the DI.
ThanksBuckeye hydro, so ur saying to just remove the DI all together?
 
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Thanks Buckeye Hydro, so you're saying to just remove the DI all together?
Yes. And assuming you don't have a pressurized storage tank, remove the carbon filter that comes AFTER the RO membrane. If you are up for a little replumbing, connect the post carbon so it is before the RO membrane.
 
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eddieg115

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First, let's start with a little jargon: Rejection Rate.
Rejection Rate is the percentage of TDS the membrane does not allow to pass through to the purified water side of the membrane.

Most residential RO membranes has a factory spec rejection rate of 96 to 99%. So if your tap water reads 267 ppm tds, and your RO water reads 7 ppm tds, you have a 97% rejection rate.

So the TDS of the RO water is hugely affected by the TDS of your feed water. It doesn't really make sense to say something like "If your RO water isn't under 10 ppm something is wrong with your RO."

How much does tap water TDS vary across the country? We have customers with tap water below 50 ppm, and some over 2,800 ppm.

Russ

So you're saying the RO is effective enough to completely construct a water profile from scratch using brewing salts?
 

Cavpilot2000

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RO is rarely, if ever, zero TDS.
If you expect it to be, you will be disappointed 99.99999999% of the time.
Whoever told you it should be zero sold you a bad bill of goods. Period.
It's close, but not zero.
If you want zero TDS, get distilled.
 

day_trippr

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True - an RO membrane alone is unlikely to hit zero without down-sides.
But, tack on a DI stage, et voila! You got your zero TDS.
Which has its own set of issues to deal with, and is totally unnecessary for brewing beer...

So you're saying the RO is effective enough to completely construct a water profile from scratch using brewing salts?
Russ didn't say that. But I totally will. It's what I (and lots of others here) have been doing for years...

Cheers!
 

CaddyWampus

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So since this thread is focused on home RO systems, I am curious about something.

The two units we have at work use various chemical injections to ensure membrane life. One of those chemicals is sodium bicarbonate, which eliminates chlorine in the feed water as it is detrimental to the life of the membranes.

Are residential RO systems not sensitive to chlorine? Or do these systems come with charcoal filters to scrub the feed water?
 

Rob2010SS

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So since this thread is focused on home RO systems, I am curious about something.

The two units we have at work use various chemical injections to ensure membrane life. One of those chemicals is sodium bicarbonate, which eliminates chlorine in the feed water as it is detrimental to the life of the membranes.

Are residential RO systems not sensitive to chlorine? Or do these systems come with charcoal filters to scrub the feed water?
When I called Russ at Buckeye Hydro and talked through my system, there was a filter option to take care of the chlorine IF i was on city water. However, I'm on well water so it wasn't needed. So mine only has the 2 filters but that 3rd filter is an option if needed.
 
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Yes - residential RO systems are configured with carbon prefilters. A "prefilter" is any filter that treats the water before the water reaches the RO membrane." For commercial RO systems, including those at breweries, we typically install an auto-backwashing carbon tank. It is much more economical in the long run rather than replacing carbon cartridges, and the tanks can be sized to treat very high flows.

Russ
 

Bilsch

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We'll respectfully disagree with that.
I kinda thought you might but I'm very happy with my choice because it takes this...

pH 7.5
Total Dissolved Solids (TDS) Est, ppm 110
Electrical Conductivity, mmho/cm 0.18
Cations / Anions, me/L 1.9/ 2.1
Sodium, Na 9
Potassium, K 2
Calcium, Ca 19
Magnesium, Mg 6
Total Hardness, CaCO3 73
Sulfate, SO4-S 6
Chloride, Cl 6
Carbonate, CO3 < 1.0
Bicarbonate, HCO3 94
Total Alkalinity, CaCO3 77

and turns it into this at .7 gallons per minute

pH 6.7
Total Dissolved Solids (TDS) Est, ppm 7 (actual measured, 2 ppm)
Electrical Conductivity, mmho/cm 0.01
Cations / Anions, me/L 0.1/ 0.1
Sodium, Na 1
Potassium, K <1
Calcium, Ca 1
Magnesium, Mg <1
Total Hardness, CaCO3 3
Sulfate, SO4-S <1
Chloride, <1
Carbonate, CO3 < 1.0
Bicarbonate, HCO3 <1
Total Alkalinity, CaCO3 <1

These numbers are from Ward Labs.
 
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day_trippr

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Is there something missing from the source water report that would make the reason why an RO system is being used more evident?
I mean, that's pretty respectable water already...

Cheers!
 

schematix

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Is there something missing from the source water report that would make the reason why an RO system is being used more evident?
I mean, that's pretty respectable water already...

Cheers!
#1 - his alkalinity is a little high for pale beers

Then there are other general benefits of RO:
#2 - RO makes your water more consistent. Some water sources vary quite a bit with the seasons as either the source water changes or the supplier changes their sources.
#3 - RO filters out most contaminants that while the EPA may say are within safe limits, you may decide you'd rather not consume.
 

day_trippr

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"A little high" can be managed with acid :)
ftr, I brew exclusively with my RO system water, but my TDS is 300+ on a good day with RA ~150, and the iron content is borderline.
I didn't have a viable option...

Cheers!
 
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