Top Off/Dilution Water pH?

[Mashmellow]

I have a 7.5 gallon Anvil Kettle, and I'd like to try a BIAB in it. In order to get the volume I want for my fermenter I'll need to add a about half a gallon of water to roughly 5.5 gallons of wort left in the kettle after removing the grains and bag. I can do the Gravity dilution calcs, but I'm wondering about the water chemistry bit. I use RO water at about 7.8 pH. Would you adjust the pH below 6 like sparge (Again, not spraging, I'm just diluting), or would you just make all the salt additions to the total amount needed and drain off the 1/2 gallon in a separate container to add back after mashing, or would you just say "<10% addition, don't worry about it--the difference is not worth the worry." Thanks

 

[Zambi]

Take my answer with a bag of salt...
I don't think you need to worry as RO water has no bicarbonates and therefor no buffering capacity...

But I may be wrong...

 

[BarbarianBrewer]

Unless you have bad water, I wouldn't worry about any volume of top-off water. Except that I might add bit of a campden tablet to take care of any chlorine/chlormine.

 

[Minbari]

I use RO for topup water, never had an Issue. Ph isn't going to change to matter

 

[Donoroto]

Except for chlorine/chloramine, it won't matter much.

Water does not have a lot of buffering power. By that I mean that the pH can change very easily, and anything in the water will be overwhelmed by what is in the wort.

I use brewing salts in every batch. My process is that I put in all the water that I'm going to need at the start, add all of my brewing salts, and then drain off what I'm going to use for the Sparge/rinse/make up water.

 

[Yooper]

RO water is fine. The pH is immaterial, since the alkalinity is low. I sparge with 100% RO water if I'm sparging. Topping off with RO water is fine also.

 

[Mashmellow]

Take my answer with a bag of salt...
I don't think you need to worry as RO water has no bicarbonates and therefor no buffering capacity...

But I may be wrong...

RO water is fine. The pH is immaterial, since the alkalinity is low. I sparge with 100% RO water if I'm sparging. Topping off with RO water is fine also.

Thanks. Kinda what I was thinking, but I've been wrong before.

Except for chlorine/chloramine, it won't matter much.

Water does not have a lot of buffering power. By that I mean that the pH can change very easily, and anything in the water will be overwhelmed by what is in the wort.

I use brewing salts in every batch. My process is that I put in all the water that I'm going to need at the start, add all of my brewing salts, and then drain off what I'm going to use for the Sparge/rinse/make up water.

That's good advise thanks. I wondered if I should rinse instead of top up, just to improve the efficiency a bit. I mostly make darker malty brews. I give this a try.

 

[Zambi]

Yes you can!
I do rinse/clean/sparge my grains with an amount of water that I know fits my kettle.
Then dilute in the fermenter (and sometimes at boiling water during the boil).
My dilution into the fermenter serves 2 purposes:
1- to bring the SG to where I want it
2- to help with the temperature (I use pre-boiled fridge water)

 

[Donoroto]

Thanks. Kinda what I was thinking, but I've been wrong before.

That's good advise thanks. I wondered if I should rinse instead of top up, just to improve the efficiency a bit. I mostly make darker malty brews. I give this a try.

It will certainly get just a bit more from the grain. It just takes a little time: if you need an extra gallon, pour in just a bit more than that, because it will take a long time for All of the water to rinse through, but 90% of it will fall in 5-10 minutes. Once volume or gravity is good* just remove the grain competely.

*rinsing still lowers gravity, as the rinse water is definitely less concentrated than The wort. But, you'll still get some extra sugars by rinsing. For us cheapskates, this is a double bonus!

 

[Bigbre04]

RO Water is unnecessary. Street water 98% of the time is more then sufficient. if anything a campden tablet as was said above is all i would bother with.

The issue with RO water is that you still have add back salts. So you just end up adding more salts.

I have made a ton of styles using the exact same salts and street water and they are generally very true to style. Water chemistry can make a difference, but it isn't the end of the world.