[brewinhard]

Sorry for the confusing topic here.

I mash in a 10 gallon gott cooler and typically chill down water the night before to add to the mash if I need to bring the temperature down.  Now that I have been working on treating my water properly (using RO water and building with salt additions from there), I was curious if I can just use straight RO water that has been chilled without adding any salts to it to adjust my mash temps down, or will this greatly affect the profile and targeted mash temp I have worked for on BrunWater? 

Mind you the amount of chilled water I typically use might be around 1 pint or so at most.  Just wondering if I need to treat the chilled water as well?  Thanks as always for your generous wisdom...

[pete b]

I use a food chiller if my mash temp ends up too high. Its made of food grade plastic and I don't need to worry about dilution. It also speeds wort chilling.
http://www.webstaurantstore.com/san-jamar-rcu64-rapi-kool-64-oz-rapid-cooling-paddle/27112870.html

[kramerog]

Dilution with RO should have almost no affect on mash pH so go ahead and do it.

[HoosierBrew]

I think you get more bang for your buck with ice cubes. Bigger temp differential. Only takes me a few to drop a degree or two F.

[denny]

I think you get more bang for your buck with ice cubes. Bigger temp differential. Only takes me a few to drop a degree or two F.

THIS^^^^

[mabrungard]

I have to assume that your temperatures are only a few degrees off and a small quantity of water is added. Since you are using RO water that has little alkalinity, its effect on pH should be minor. However, there could be a slight increase in the mash pH since you are diluting the acid content. The same thing occurs when mashing with a thick versus thin grist ratio.

Of course, you would be diluting the ionic content that you were targeting with the original mineral additions, but if the cool water addition is small in comparison to the total mashing water volume, then the effect will also be small.

It doesn't sound like this is a serious concern. I do agree with the others that recommend using ice cubes since there is greater temperature reduction per unit of added water.