Recipe and water adjustment feedback

I'm going to be brewing a pale ale on Sunday, and I plan to build up my water from RO. It is the first time I'm doing this so I'm hoping somebody can look over my numbers and verify a few things for me so I can be sure I'm understanding right.

Recipe feedback is appreciated too.

The reason for the crystal 120 and crystal 40 is they are what I have on hand and I want a little darker than just the 4 oz of 40L.

For the FWHs I changed the boil time to 20 mins to lower the IBUs, what I've read suggests that this is the best way to approximate the bitterness.


Recipe:
Batch Size (fermenter): 3.50 gal
Estimated OG: 1.045 SG
Estimated Color: 6.3 SRM
Estimated IBU: 30.5 IBUs
Boil Time: 60 Minutes

5 lbs 8.0 oz - Pale Malt (2 Row) US (2.0 SRM) 89.8 %
2.0 oz - Acid Malt (3.0 SRM) 2.0 %
4.0 oz - Honey Malt (25.0 SRM) 4.1 %
3.0 oz - Caramel/Crystal Malt - 40L (40.0 SRM) 3.1 %
1.0 oz - Caramel/Crystal Malt -120L (120.0 SRM) 1.0 %

mash 60 min @ 152F

0.50 oz - Cascade [5.50 %] - FWH 9.7 IBUs
0.50 oz - Cascade [5.50 %] - 60.0 min 14.6 IBUs
0.75 oz - Cascade [5.50 %] - 5.0 min 4.4 IBUs
0.75 oz - Cascade [5.50 %] - 2.0 min 1.9 IBUs

0.50 oz - Cascade [5.50 %] - Dry Hop 7.0 Days (maybe)

WLP090 San Diego Super Yeast


Sorry for the mess that's about to follow, I'm trying to explain my thought process and work process to help fix any flaws.
Water: On the water I am aiming for Bru'n Water's Pale Ale Profile.
Ca 165 ppm
Mg 18 ppm
Na 25 ppm
SO4 300 ppm
HCO3 180 ppm

Using beersmith & 6 gallons of RO water (2 mash, 4 sparge), then rounding the numbers a bit for simplicity, adding the following puts me pretty close:
7.8 g gypsum
4.8 g epsom
3 g calcium chloride
1.2 g baking soda
3.6 g chalk

When I switch back over to Bru'n water and put in those numbers in I get a huge discrepancy in the bicarbonate that the chalk provides. According to beersmith it is 95 ppm, according to Bru'n water it is 193.4 ppm. EZ water's numbers were closer to beersmith when I put the data in there.

My plan, using Bru'n waters gram/gal and checking off the box to recalculate gypsum and calcium chloride use for the sparge water, is to mix:

Mash water:
2 gal RO
2.6 g gypsum
1.6 g epsom
.4 g baking soda
1 g calcium chloride
1.2 g chalk

Sparge water:
4 gal RO
8.3 g gypsum
3.2 g epsom
2.9 g calcium chloride


My main concern with the water is the bicarbonate ppm discrepancy I am running into. Which should I trust?

I've read recommendations against using chalk and have tried a couple grocery stores for pickling lime but haven't found any. If I do I will redo these numbers. I mostly understand what I read about chalk not dissolving well, but once the grains are added and the mash starts to acidify as sugars are converted, will that help the chalk to dissolve?

Thank you

 

The Bru'n Water bicarbonate numbers are only accurate if you're going to the trouble of dissolving the chalk into the water with CO2. If you're not doing that, then the instructions suggest doubling the amount of chalk to make up for the discrepancy. The numbers that Beersmith and EZ Water are quoting for the bicarb from chalk assume that the CO2 step is not being performed.

To get similar results between all those programs, In Bru'n Water dial in half the amount of chalk used in Beersmith or EZ and the bicarb concentrations will then be similar.

Walmart is also a source for pickling lime, but its seasonal. Given that its harvesting and canning time, you might find it there. Don't be afraid to ask the store management if they have pickling lime. My grocery store had it a place I would have never looked. Another option is to order it direct from Amazon or from Mrs Wages. That 1 lb canister should be enough to last years.

 

What's the rationale for having the bicarbonate that high? I know there's some concern in darker beers that you need it for buffering to avoid too low of a pH, but for a pale ale does it really need to be there? It seems like you'd be working at cross purposes with the acid malt.

 

Thanks Martin,
That's what I was wondering about with chalk but wasn't quite sure how to phrase it.

I'm not sure about the high bicarb for the target profile actually. It caught my eye too but as I'm just starting with any serious water adjustment I'm more concerned with hitting the target profile than with understanding it 100%. Martin and others on this board know a lot more about what chemistry than I ever will, so I'm putting trust in the target profiles he provides.

I started using acid malt and doing some dilutions in my lighter beers after reading the water chem primer. In this case, and using the Bru'n Water mash acid adjustment sheet, it should keep me in the 5.2 to 5.4 mash pH range when using no chalk up to .6 g/gal chalk, a bit of a safety net if you will.