pre mash-in ph at 5.1?

[sushieater]

I'm doing my first attempt at water adjustments. I used brun water to calculate my additions based on my city water report.

Before mash-in the ph of my water measured 5.1. I was expecting 5.46. Is that a correct assumption? Did something go wrong? Starting water read correctly at 7.6

Should I try to bump the ph w/ baking soda? I'm not sure the best way to calculate this.

I do biab so I treated all 32.5L of strike water. I let it sit overnight and mixed it good after adding the additions.

5.9g calcium chloride
2g gypsum
7.8ml lactic acid

I'm making a NE style IPA. 23L in fermenter.
85% 2 row
10% wheat
5% honey malt

Wanted to try heavy chloride to sulfate ratio like I saw in this thread.
https://www.homebrewtalk.com/showthread.php?t=517721

Thanks! Was planning to brew this tonight.

 

[sushieater]

I got the expected 5.46 ph by removing my grain bill. Brun water said my expected ph would be 5.46. Is this a valid way to get my pre dough-in ph? I tested the water again and its reading 5.3 now

 

[Yooper]

I got the expected 5.46 ph by removing my grain bill. Brun water said my expected ph would be 5.46. Is this a valid way to get my pre dough-in ph? I tested the water again and its reading 5.3 now

The pH of the starting water has no real bearing on the mash pH. What determines the mash pH is the acidity of the grains (especially roasted grains) and the mash water's alkalinity.

Don't even take the pH of your water, unless you are acidifying your sparge water and need to keep it below 6 (or using RO water for the sparge). It's only stressing you out!