Dilution vs additions?

[ampsman]

I just got my water report as follows:

pH 7.9
Total Dissolved Solids (TDS) Est, ppm 402
Electrical Conductivity, mmho/cm 0.67
Cations / Anions, me/L 6.4 / 6.4
ppm
Sodium, Na 77
Potassium, K 4
Calcium, Ca 30
Magnesium, Mg 18
Total Hardness, CaCO3 150
Nitrate, NO3-N 0.9 (SAFE)
Sulfate, SO4-S 25
Chloride, Cl 97
Carbonate, CO3 < 1.0
Bicarbonate, HCO3 118
Total Alkalinity, CaCO3 98
Total Phosphorus, P 0.25
Total Iron, Fe < 0.01

Looking at this it makes sense that I have been having more success with darker maltier beers and my IPA's are falling flat.
Using palmers spreadsheet it seems like I might be fine with a 50% RO dilution rather than needing any additions. Any thoughts?

 

[GlowingApple]

I plugged your values into Bru'n water, with 50% RO dilution, and compared the final numbers to the pale ale profile. They come out pretty close, provided you add some calcium sulfate (gypsum).

Targets:
Ca=140ppm; Mg=18ppm; Na=25ppm; SO4=300ppm; Cl=55ppm

Your water with 50% RO water and 1.90g gypsum/gal:
Ca=132ppm; Mg=9ppm; Na=43ppm; SO4=293ppm; Cl=51ppm

Depending on your grain bill, the RO water and the gypsum would also help bring down the mash pH.

 

[ajdelange]

It is impossible to talk about hitting a profile without specifying the desired profile pH. Assuming mash pH is a good target (as it reduces alkalinity WRT mash to 0) the exact target numbers in #2 can be attained using common salts (including calcium carbonate and sodium bicarbonate) and 4.5 L of dilution water for each liter of the source in #1 but some HCl and H2SO4 are required. Given that one is going to use 4.5 L RO water for each liter of source he might as well use 100% RO in which case the exact numbers in #2 are again attainable but without any HCl or H2SO4 but some calcium carbonate and lactic or phosphoric acid are required. This is because the ratios of the ions in the target are not consistent with the ratios of chloride and sulfate in CaCl2 and CaSO4. Adding the calcium carbonate and then neutralizing it with the acid gives exact numbers for all the specified ions at the expense of some lactate or biphosphate.

In any case one can usually get to whatever profile he wants by the addition of salts including dihydrogen monoxide but the calculations necessary often go beyond what the popular spreadsheets are set up to do. Calculations are much simplified if one starts with RO water - the so called 'blank sheet of paper'.

 

[ampsman]

I plugged your values into Bru'n water, with 50% RO dilution, and compared the final numbers to the pale ale profile. They come out pretty close, provided you add some calcium sulfate (gypsum).

Targets:
Ca=140ppm; Mg=18ppm; Na=25ppm; SO4=300ppm; Cl=55ppm

Your water with 50% RO water and 1.90g gypsum/gal:
Ca=132ppm; Mg=9ppm; Na=43ppm; SO4=293ppm; Cl=51ppm

Depending on your grain bill, the RO water and the gypsum would also help bring down the mash pH.

are we talking total water volume when you talk about additions/gallon? It should be noted I am doing no sparge BIAB.

 

[GlowingApple]

Ppm is a measure of concentration so if you're diluting with 50% RO water, then regardless of the volume you'd have these values. For the gypsum, Bru'n water calculates a grams per gallon addition as well as a total addition. You can set your volume of mash water to the full volume and it will give you the amount you'd need.

As for pH, that's a different story. More water in the mash means more alkalinity that can neutralize the acid in the grain, so likely just gypsum wouldn't be enough to lower the pH. You'd probably have to add some lactic acid or phosphoric acid as well. I ended up switching to 100% RO water, and adding in the necessary salts, because my tap water was just too alkaline for a full-volume BIAB.

Bru'n water 1.16b is free, so you might want to give it a try and plug in your actual volumes and grain bill to see: https://sites.google.com/site/brunwater/