Bru'n Spreadsheet help - bicarbonate is negative

[TravelingLight]

I'm finally trying to dial in some water adjustments. For this beer (since I am waiting on a Ward Labs report), I'm building up RO water to how I want it.

I've got the sulfate and chloride pretty much where I want it. Calcium is fine where it is. Not worried about the Mg, I know I'll get some from the grain. But what I am concerned about is the -68 bicarbonate. First of all, is that a problem? It only affects ph, yes? So if the ph is fine does it matter what the bicarb is? If I need to adjust it, any guidance? See attached for the screenshot. Thanks.

 

[jerbrew]

https://www.homebrewersassociation.org/forum/index.php?topic=15647.0

couple answers down the man himself answers that question

 

[PlinyTheMiddleAged]

Don't worry about the negative bicarbonate. You are correct - it's the pH that counts.

 

[TravelingLight]

https://www.homebrewersassociation.org/forum/index.php?topic=15647.0

couple answers down the man himself answers that question

Spot on. Thank you!

Don't worry about the negative bicarbonate. You are correct - it's the pH that counts.

Excellent that's what I needed to know. Thanks.

 

[dmtaylor]

EDIT: Oops, nevermind my previous statement in this space. Unable to delete this #5 for some reason.

 

[ajdelange]

Martin uses bicarbonate as a proxy for alkalinity. Alkalinity is a proton deficit i.e. a measure of how many protons you need to supply to reach a lower pH. Negative alkalinity is thus a proton surfeit i.e. how many protons you need to absorb to reach a higher pH. Thus negative bicarbonate here means negative alkalinity and thus an excess of protons. If he would label it 'alkalinity as bicarbonate' it would make sense but he won't and many are, therefore, confused.

 

[TravelingLight]

Martin uses bicarbonate as a proxy for alkalinity. Alkalinity is a proton deficit i.e. a measure of how many protons you need to supply to reach a lower pH. Negative alkalinity is thus a proton surfeit i.e. how many protons you need to absorb to reach a higher pH. Thus negative bicarbonate here means negative alkalinity and thus an excess of protons. If he would label it 'alkalinity as bicarbonate' it would make sense but he won't and many are, therefore, confused.

That makes sense. Well, maybe not entirely but it answers my questions. Thank you.