Brewfather sparge calculations?

[Ken Loves Craft Beer]

Hi there. Hoping someone has a take on this. When I use brewfathers built in water adjustment tool to get the right amount of mineral additions for my RO water, and check the "don't calculate for sparge water" or whatever it is, does it assume that I'm then doing BIAB and not factor in the extra 12 litres or so that I'm going to sparge with? (Using a 35 gen 4 brewzilla) Does that make sense? I don't want to treat the sparge water but is it under suggesting the amount of additions I should be using by not expecting the extra water that will be going in?
I'm finding that by following its suggestions that I am having to use 5 or 6 ml of lactic to get the ph it predicts rather than the 2 or 3 it recommends.
I've done 3 brews with this hardware so far, with 3 different yeasts and they have all under attenuated so I'm trying to rule out if a lack of minerals may be contributing. Cheers.

 

[wide eyed and legless]

Under attenuated is not necessarily just about minerals, could be mash temperature grain crush and listening to Palmer a lack of magnesium. Have you tried treating the whole water volume together and then removing what you are going to sparge with?

 

[TwoCrows]

If your calcium is around 50ppm and your happy with the sulfate to chloride ratio let it ride.
I would double check your mash temperature, if high you are in Alpha territory your beer will finish with a higher gravity.
I do use a yeast nutrient. But there are loads of beneficial minerals present from normal mashing.

 

[Ken Loves Craft Beer]

I'm not suggesting that the mineral composition is the problem yet, just double checking all possible causes. All 3 brews have used different mash temps ranging from 62 to 67 on the latest one and I'm using the Bluetooth KL thermometer with my BZ so I'm pretty sure the mash temp is consistent and fairly accurate. All yeasts used (US 05, Verdant and Novalager on the current one) were well within use by dates. I also use yeast nutrients and have pretty tight temp control using the rapt pill with the rapt temp controller.
Also how fast do your ferments go? I see so many videos saying things like "verdant hit fg in 4 days" or "novalager is a beast, fg 3 days later" but none of mine have gone like that. My current IPL with Nova was pitched last Saturday but it's only just got to 1020 after 7 days.(68% attenuation)
But to my main point, are the mineral adds being suggested by brewfather taking into account the sparge water to be added or am I diluting it more than it expected, leading to the higher than predicted ph? Maybe next brew I could just use carbon filtered tap water and see how the yeast responds...

 

[TwoCrows]

I use Beersmith so not up to speed with Brewfather.
It should state for the mash only and should take into account for the base line water that you have imputed for the sparge.
Yes more calcium to lower the ph, more acid if not.
Alkalinity is a factor and helps to stabilize the ph.

I have a Helles on the go with Diamond yeast, after 4 days I raised one degree a day until day 7-8.
Crash chill 3 degrees a day until you reach 1-4 degrees. The yeast is still working and cleaning up.

Also confirm that your temp control on the fermenter is correct. I have had this issue with lower than wanted temps.

 

[wide eyed and legless]

I don't know if you have read this article.
https://byo.com/article/brewing-with-reverse-osmosis-water/
Also the timing of adding the chloride to the mash liquor is important, apparently it takes four hours to fully dissolve.

 

[TwoCrows]

Your software should get your mash Ph correct. If you don't correct the sparge water you will lower the Ph of the total wort, check Ph preboil?

 

[Ken Loves Craft Beer]

Your software should get your mash Ph correct. If you don't correct the sparge water you will lower the Ph of the total wort, check Ph preboil?

Ahh that's a good idea. Will check next brew.

 

[razz]

Good morning KLCB. How much yeast are you pitching into those three brews?

 

[Ken Loves Craft Beer]

Good morning KLCB. How much yeast are you pitching into those three brews?

All have had 2 packs. Thats pretty much my go to amount for everything. Haven't done a liquid one on the BZ yet obviously

 

[Ken Loves Craft Beer]

Just as an update, my IPL appears to have hit final gravity now after 8 days, 1015 from 1061 which is still not as low as I was hoping (apparent attenuation is 74% , lower than the Novalager specs which state 78-84). Is it fair to assume that irrespective of mash temp differences that my FG should at least fall somewhere in that Lallemand range? I know it's only 4% off, but I really want some consistency and predictability going forward.
The beers I have made so far have been very tasty, but this piece of the puzzle has me stumped. I was a BIAB brewer for quite a few years before getting the Brewzilla this year, and never had this problem before.

 

[razz]

I use Nova and pretty much always get 80% att. With the blt and built in thermometers I’ve had a couple of swings in mash temp range, anything from 65-69. If you are getting much bigger variations then you may need to calibrate them. With Brewfather water additions I’m pretty much bang on with what it recommends and what my pH measures. Pale beers are 5.2 and I make sure the wort in the fermenter starts at 5.