# LoDo Techniques

### Help Support Homebrew Talk:

#### Dustin_J

##### Well-Known Member
Need some help with basic math.

Sad to admit, it's been over 50 years since I struggled through college math. I'm stuck in an endless Do Loop (been 50 years since I did FORTRAN coding as well) and can't figure out where I'm making my error. It's not Diffy Q. Not even advanced calculus. We're talking basic algebra. Somebody help bail this 70 year old brain out of dementia.

Background: Trying to determine how much additional sodium (PPM) will be needed to account for in a brewing water calculation. From the LoDO brewing website, I know that 1 mg NaMeta solute in 1 liter of water results in 24 PPM additional sodium. My target volume is 23 liters, strike volume ~29.5 liters. I add .65 grams of NaMeta to my strike water to scavenge DO prior to mash-in. How many PPM does this increase the amount of sodium in both the strike water and final concentration in post boil wort? Solve. {Please show work}.

Brooo Brother
Hi Brooothru,
Keep in mind that, in water, 1mg/L ~= 1ppm. So, 1 mg of NaMeta in 1L of water yields ~.24 ppm sodium, whereas 100 Mg of NaMeta in 1L of water yields ~24 ppm sodium.

To get there, the NaMeta (SMB) molecular formula is Na2S2O5

The Elemental/Atomic masses of constituent elements are:
Na: 22.9897
S: 32.065
O: 15.9994

So, for Na2S2O5:
-Na: 22.9897*2: 45.9794
-S: 32.065*2: 64.130
-O: 15.9994*5: 79.997
45.9794 + 64.130 + 79.997 = 190.1064 = Total molecular mass of NaMeta

The Percentage Na in NaMeta, then (by mass):
- 45.9794/190.1064 = .2419. or ~24.2% Na by mass
So 1 mg of NaMeta in 1L of water should yield ~.242 ppm (Mg/L) of Na

.65 grams of NaMeta added to 29.5 L of water yields ~22 Mg/L (ppm) of NaMeta

Of that 22 Mg/L (ppm) NaMeta in your strike water:
- 24.2% is Na, so you're adding ~ 5.32 Mg/L (ppm) of sodium to your strike water

Final water/batch volume (~23 L) will be a product of both absorption/losses (from grain, Mash tun deadspace, tubing, transfer loss, etc.) as well as evaporation/concentration (boil off), so exactly estimating ppm NA in your finished volume is tough without knowing more. It should be somewhere between ~ 5.32 ppm (Assuming no losses are from evaporation, which isn't true) and ~6.82 ppm (assuming all losses are from evaporation, which also isn't true). The difference between these, of course, is pretty trivial.

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#### Brooothru

##### Well-Known Member
Hi Brooothru,
Keep in mind that 1mg/L = 1ppm. So, 1 mg of NaMeta in 1L of water yields ~.24 ppm sodium, whereas 100 Mg of NaMeta in 1L of water yields ~24 ppm sodium.

Final water/batch volume (~23 L) will be a product of both absorption/losses (from grain, Mash tun deadspace, tubing, transfer loss, etc.) as well as evaporation/concentration (boil off), so exactly estimating ppm NA in your finished volume is tough without knowing more. It should be somewhere between ~ 5.32 ppm (Assuming no losses are from evaporation, which isn't true) and ~6.82 ppm (assuming all losses are from evaporation, which also isn't true). The difference between these, of course, is pretty trivial.
Thanks so much for the math, Dustin. Your solution explains it quite clearly. I thought I was on the right track, but I was off by two orders of magnitude which I couldn't resolve. I was coming out with something like 540 PPM and 650 PPM respectively. I have a couple of pages of legal pad hen-scratches to sift through to discovery where I kept misplacing the decimal points. Log_8 instead of Log_6 perhaps?

But I guess that means I'm still losing my mind. Just not as fast as I feared.

Brooo Brother

#### Brooothru

##### Well-Known Member
Thanks so much for the math, Dustin. Your solution explains it quite clearly. I thought I was on the right track, but I was off by two orders of magnitude which I couldn't resolve. I was coming out with something like 540 PPM and 650 PPM respectively. I have a couple of pages of legal pad hen-scratches to sift through to discovery where I kept misplacing the decimal points. Log_8 instead of Log_6 perhaps?

But I guess that means I'm still losing my mind. Just not as fast as I feared.

Brooo Brother

Hah! Just found it. I was using the value 24 PPM instead of 0.24 PPM. Not going nuts. Just going blind.

This getting old thang' ain't for wimps!

Brooo Brother

#### Dustin_J

##### Well-Known Member
Hah! Just found it. I was using the value 24 PPM instead of 0.24 PPM. Not going nuts. Just going blind.

This getting old thang' ain't for wimps!

Brooo Brother
No worries, I go through a few of these types of exercises periodically just to make sure I'm on track as well. Good luck!

#### aeviaanah

##### Well-Known Member
Hi Brooothru,
Keep in mind that 1mg/L = 1ppm. So, 1 mg of NaMeta in 1L of water yields ~.24 ppm sodium, whereas 100 Mg of NaMeta in 1L of water yields ~24 ppm sodium.

To get there, the NaMeta (SMB) molecular formula is Na2S2O5

The Elemental/Atomic masses of constituent elements are:
Na: 22.9897
S: 32.065
O: 15.9994

So, for Na2S2O5:
-Na: 22.9897*2: 45.9794
-S: 32.065*2: 64.130
-O: 15.9994*5: 79.997
45.9794 + 64.130 + 79.997 = 190.1064 = Total molecular mass of NaMeta

The Percentage Na in NaMeta, then (by mass):
- 45.9794/190.1064 = .2419. or ~24.2% Na by mass
So 1 mg of NaMeta in 1L of water should yield ~.242 ppm (Mg/L) of Na

.65 grams of NaMeta added to 29.5 L of water yields ~22 Mg/L (ppm) of NaMeta

Of that 22 Mg/L (ppm) NaMeta in your strike water:
- 24.2% is Na, so you're adding ~ 5.32 Mg/L (ppm) of sodium to your strike water

Final water/batch volume (~23 L) will be a product of both absorption/losses (from grain, Mash tun deadspace, tubing, transfer loss, etc.) as well as evaporation/concentration (boil off), so exactly estimating ppm NA in your finished volume is tough without knowing more. It should be somewhere between ~ 5.32 ppm (Assuming no losses are from evaporation, which isn't true) and ~6.82 ppm (assuming all losses are from evaporation, which also isn't true). The difference between these, of course, is pretty trivial.
So the percentage by mass directly converts to ppm or mg/liter?

#### Dustin_J

##### Well-Known Member
So the percentage by mass directly converts to ppm or mg/liter?
In water it does, at least at ~standard temp/pressure, as 1 mL of water has a mass of 1 gram. Not so much for other liquids necessarily. Good clarification.

#### Hwk-I-St8

##### Supporting Member
HBT Supporter
Pitch the right amount of yeast and you won't have diacetyl. Simple as that.
Is it really that simple? I've had a number of moderate IPAs (OGs around 1.060) that have exhibited diacetyl issues. I always do a 2L starter of 1318 for those IPAs. I would think that would be sufficiently large yeast population for that beer.

#### tmendick

##### Supporting Member
HBT Supporter
how are you handling dry hops? You could be suffering from hop creep

#### Unicorn_Platypus

##### Urine I Pee... Eh?
Well, it depends on how we define whirlpool.

If we are whirlpooling to centrally locate trub and break material while cooling to pitching temps, then it isn’t much of an issue. You are subject to a short duration of atmospheric diffusion.

If we are talking about quadruple hop stew IPA whirlpooling, with prolonged time at higher temps for hop stands, then it would be advisable to utilize a cap similar to in the mash.
How do you initiate a whirlpool using a whirlpool arm without introducing oxygen?

When using a whirlpool arm wouldn't there be a significant amount of air in the tubing when initially run the wort out of the kettle into the pump, up into the arm, and back underneath the wort?

#### JAReeves

##### Reevesie
HBT Supporter
How do you initiate a whirlpool using a whirlpool arm without introducing oxygen?

When using a whirlpool arm wouldn't there be a significant amount of air in the tubing when initially run the wort out of the kettle into the pump, up into the arm, and back underneath the wort?
You could pump CO2 through your tubing before hooking it up.

#### Unicorn_Platypus

##### Urine I Pee... Eh?
You could pump CO2 through your tubing before hooking it up.
What kind of fittings would you need to make the work?

I'm not picturing logistically how to do it

How would you keep the CO2 trapped in the lines after flushing and then disconnecting / reconnecting to the pump & kettle?

Could you walk me through the equipment needed and what that process would look like?

#### TLaffey

##### Well-Known Member
How do you initiate a whirlpool using a whirlpool arm without introducing oxygen?

When using a whirlpool arm wouldn't there be a significant amount of air in the tubing when initially run the wort out of the kettle into the pump, up into the arm, and back underneath the wort?
Prime the pump during the boil.

#### JAReeves

##### Reevesie
HBT Supporter
I have a air compressor sprayer attachment, pretty common at any auto or hardware store, I imagine. It's attached to a hose with SS Ball lock end, so it just plugs into the grey gas QD's in my keezer. Run the hose out of the keezer and I can spray CO2 onto/into anything. I use it to prime hoses, fill up kegs or carboys that need a blanket, and start the vacuum movement of liquids from a fermenter into a keg for closed transfers. I started this gravity transfer with a two-hole plug in the barrel: one for the SS racking cane and the other got a gentle push with the CO2 until it flowed on its own.

It's one of these:

Peace,

Reevesie