LaMotte Water Test Kit value conversion

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Slapnik

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So I have this water test kit which enables me to test for the following in my water:
  • Chloride
  • Sulfate
  • Alkalinity (as CaCO3)
  • Total Hardness
  • Calcium Hardness
  • Sodium by calculation
However, when I go into BeerSmith to create a water profile it expects the following values to be entered:
  • Calcium
  • Magnesium
  • Sodium (got it)
  • Sulfate
  • Chloride (got it)
  • Bicarbonate
So my test kit only gives me values for Sodium and Chloride. Is it possible to determine the rest of the values expected by BeerSmith by calculation using the values I get from my test kit?
 
Calcium Hardness ÷ 2.5 = Ca++

(Total Hardness - Calcium Hardness) ÷ 4.12 = Mg++

Alkalinity x 1.22 = Bicarbonate
 
Without knowing anything about said test kit, just a heads up that you may have to multiply the Sulfate test result value x3 to get to ppm Sulfate for tools like Bru'n Water...

Cheers!
 
The LaMotte kit was designed for analyzing brewing water. Ward Labs analyzes farm water. So I doubt that multiplication by 3 is necessary to derive SO4 for LaMotte. But there is potentially a mathematical calculation required whereby to extract SO4 from some other combination of derived ion values.
 
In my 'Mash Made Easy' mash pH assistant software if you know the other mineral ion values with sufficient certainty (confidence), you can enter the ion values that you know and then plug in value guesses for SO4 until you finally achieve a "Good" Cation/Anion mEq/L balance check, then infer that your SO4 value is in that ballpark. Likely this should be sufficient.
 
Calcium Hardness ÷ 2.5 = Ca++

(Total Hardness - Calcium Hardness) ÷ 4.12 = Mg++

Alkalinity x 1.22 = Bicarbonate
Thank you so much for this! A few questions to make sure I'm clear:

Do these formulas assume all my derived values are CaCO3 ppm? (because they are)

I also mis-typed something above. I have Sulfate but I do NOT have a value for Sodium. Is there a calculation to get Sodium?

Also, is it possible to get a negative value for Mg++? My Total Hardness was 40 CaCO3 ppm and Calcium Hardness was 60 CaCO3 ppm. Is this possible or maybe I didn't run this test properly?
 
Last edited:
Wait, scratch the question about Sodium, I have that formula in the Test Kit, just forgot about it.

So check my Math/Thinking as I derive things from my test values, which are:

  • Chloride = 60 ppm
  • Sulfate = 0 ppm
  • Alkalinity = 100 CaCO3 ppm
  • Total Hardness = 40 CaCO3 ppm
  • Calcium Hardness = 60 CaCO3 ppm
Given these values, are these calculations correct?
  • Magnesium = (40 - 60) x .24 = -4.8
  • Sodium = 67.022 (per formula in test kit)
  • Bicarbonate = Alkalinity x 1.22 = 122
  • Calcium = 60 x .4 = 24
 
Wait, scratch the question about Sodium, I have that formula in the Test Kit, just forgot about it.

So check my Math/Thinking as I derive things from my test values, which are:

  • Chloride = 60 ppm
  • Sulfate = 0 ppm
  • Alkalinity = 100 CaCO3 ppm
  • Total Hardness = 40 CaCO3 ppm
  • Calcium Hardness = 60 CaCO3 ppm
Given these values, are these calculations correct?
  • Magnesium = (40 - 60) x .24 = -4.8
  • Sodium = 67.022 (per formula in test kit)
  • Bicarbonate = Alkalinity x 1.22 = 122
  • Calcium = 60 x .4 = 24
Total hardness must be greater than Calcium hardness.

2.5(Ca ppm) + 4.12(Mg ppm) = Total Hardness
 
You can't have negative minerals.

Yes, Hardness and Alkalinity are Measured in units of CaCO3.

It would be very highly unusual for natural water to have zero ppm SO4.
 
You can't have negative minerals.

Yes, Hardness and Alkalinity are Measured in units of CaCO3.

It would be very highly unusual for natural water to have zero ppm SO4.
I should mention the water is from my tap, run through a filter. But as mentioned, I think I need to run the tests again.
 
2.5 x Ca++ mEq equilibrates Ca++ to CaCO3.

4.12 x Mg++ mEq equilibrates Mg++ to CaCO3.
 
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