Does Reverse Osmosis water contain any ions at all? - Home Brew Forums
Home Brew Forums > Home Brewing Beer > General Techniques > Does Reverse Osmosis water contain any ions at all?
Sign-up To NEW HBT Article Newsletter - Brewing Articles Direct To You!

Reply
 
Thread Tools
Old 05-30-2010, 12:08 AM   #1
hokenfloken
Feedback Score: 0 reviews
Recipes 
 
Join Date: Feb 2009
Location: Charlotte, Michigan
Posts: 80
Likes Given: 4

Default Does Reverse Osmosis water contain any ions at all?

Greetings! I've been searching the forum for awhile now and I cannot find any definitive answer to this question.

I currently build my water from distilled water and brewing salts. I would like to start using RO water due to the lower cost.

Can I expect RO water to be nearly free of salt ions?

Any experienced advice would be greatly appreciated. Thank you very much.


hokenfloken is offline
 
Reply With Quote
Old 05-30-2010, 12:30 AM   #2
Special Hops
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jun 2008
Location: Kanatenah
Posts: 1,426
Liked 22 Times on 20 Posts
Likes Given: 3

Default

http://en.wikipedia.org/wiki/Reverse_osmosis


Special Hops is offline
 
Reply With Quote
Old 05-30-2010, 12:37 AM   #3
hokenfloken
Feedback Score: 0 reviews
Recipes 
 
Join Date: Feb 2009
Location: Charlotte, Michigan
Posts: 80
Likes Given: 4

Default

Thanks for the wikipedia link, although I have read it already. I guess my question whether or not any of the salt ions are smaller than 0.1 nm. If they are larger, they will be filtered out. If not, they will pass though, or at least that's my interpretation. If RO water is essentially free of ions then what is the point of distilled water? Thanks.
hokenfloken is offline
 
Reply With Quote
Old 05-30-2010, 11:01 AM   #4
artbrau
Feedback Score: 0 reviews
Recipes 
 
Join Date: Apr 2009
Location: Morristown, NJ
Posts: 104
Liked 6 Times on 4 Posts

Default

I believe distillation and RO are two different processes that get you to the same place.
artbrau is offline
 
Reply With Quote
Old 05-30-2010, 01:02 PM   #5
remilard
Feedback Score: 0 reviews
Recipes 
 
Join Date: Nov 2008
Location: Kansas City
Posts: 3,654
Liked 43 Times on 41 Posts

Default

Quote:
Originally Posted by hokenfloken View Post
Thanks for the wikipedia link, although I have read it already. I guess my question whether or not any of the salt ions are smaller than 0.1 nm. If they are larger, they will be filtered out. If not, they will pass though, or at least that's my interpretation. If RO water is essentially free of ions then what is the point of distilled water? Thanks.
RO doesn't exclude particles solely on the basis of size, so your interpretation isn't quite correct.

The answer to your question is that the water will not be ion free, there will be lower ion content than there was before, it will probably be very low (single digits ppm for each ion), and it is impossible to predict exactly what it will be.
remilard is offline
 
Reply With Quote
Old 05-30-2010, 02:52 PM   #6
Hoppocrates
Feedback Score: 0 reviews
Recipes 
 
Join Date: May 2010
Location: Coralville, IA
Posts: 93
Default

A member of my home brew club sent the supermarket RO refill station water to the lab. It was surprisingly incredibly efficient and nearly distilled. You can see the results at the bottom of this page:

http://www.thirstyhomebrew.org/
Hoppocrates is offline
 
Reply With Quote
Old 05-30-2010, 06:00 PM   #7
bad coffee
HBT_LIFETIMESUPPORTER.png
Feedback Score: 0 reviews
 
bad coffee's Avatar
Recipes 
 
Join Date: Jun 2008
Location: NYC
Posts: 5,055
Liked 474 Times on 463 Posts
Likes Given: 48

Default

IF you're using RO-DI (DeIonized) water it should be 0 PPM. If it's just RO, then it will depend on the membrane.

(From my aquarium knowledge)
A 100GPD (Gallon per day) filter has a 90% rejection rate.
A 75GPD has a 97% rejection rate.

So depending on the membrane, you might be getting really good water or just good water. YMMV.

B
__________________
Quote:
Originally Posted by GilaMinumBeer
Why do you think they choose that path? (.)(.) = $$$$$$$$$
Quote:
Originally Posted by Zuljin View Post
Wtf was chasing you for an hour? Buy a gun already.
Quote:
Originally Posted by AZ_IPA View Post
I'm a meat hunter. PKU.
bad coffee is offline
 
Reply With Quote
Old 05-30-2010, 10:03 PM   #8
GreenMonti
Feedback Score: 0 reviews
Recipes 
 
Join Date: Nov 2009
Posts: 1,062
Liked 10 Times on 10 Posts
Likes Given: 2

Default

I have a RO/DI unit for my reef aquarium. Every time I fire it up I hit the TDS meter to check my incoming and outgoing TDS rate. Since day one I get 0 PPM on the outgoing.

The above post about the membrane is correct. I also believe the quality of the membrane has to do with its rejection rate.


GreenMonti is offline
 
Reply With Quote
Reply

Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Chlorine in Reverse Osmosis Water? jescholler Brew Science 11 02-01-2010 01:02 PM
Reverse Osmosis / DI Water Cytosol Beginners Beer Brewing Forum 3 07-08-2009 09:30 PM
Reverse Osmosis Water eschatz Recipes/Ingredients 17 07-11-2008 05:47 PM
Reverse Osmosis water usage? RotorHead6 All Grain & Partial Mash Brewing 12 10-28-2007 11:29 PM
Reverse Osmosis Water Filtration Fatboy Equipment/Sanitation 6 08-26-2005 01:49 PM


Forum Jump