RO Water VS Distilled - Page 2

thdewitt · 02-24-2009, 02:57 AM

Thanks everyone for the help. So in working with Palmers Spreadsheet and distilled water I come up with the following additions for 10 gallons of water. Epsom Salt .7 gm, Calcium Chloride .4 gm, Baking Soda .3 gm, Chalk .4 gm. With that the water would be:
CA 7.1, MG 2, Na 2.2, S04 7.2, Cl 5.1, and HC03 12. This is very close to Pilsen water. My problem now. Those are pretty small amounts. I need a much better scale. Does that small of an amount really make a difference. It seems like RO water would have at least this much without additions.

Yes, I am an all grain brewer. Now with the 10 gallons I can use some for the mash and some for the sparge. Do you need to treat the sparge water. I think you would as it will ultimately be in the boil and the sulfate/chloride ratio seems to affect the malty/bitter taste perception.

RobBug · 02-24-2009, 03:47 AM

Just stumbled on this post and thought I would toss in what I know. I am a nuc machinist's mate on a sub and I can definitely attest that DI water is the purest you can get. RO is good but as stated earlier you end up with some dissolved solids as the membranes are not 100% efficient. Distilled is from flash evaporators or low vacuum systems. The inherent drawback to these systems is that with low vacuum, you get high velocity steam up into the upper distillate cooler. Invariably you end up with some "carryover". Where I work at, we take our distillate from our evaporators (distilled water) and run them through cation/anion exchangers (de-ionized water). Once through those we end up with <0.1 ppm of anything (we look for Chlorides).

So in a nutshell from not so pure to pure:
Reverse Osmosis/Distilling
De-ionized water

Sorry for the techno-babble.

Rob