"LFS" branded Magnesium mix - confused on final potency for dosing

Kyl · Jun 14, 2018

I've tried to do the mental math to figure out how this relates to the other two part magnesium mixtures out there (Mg Chloride + Mg Sulfate), but I have to concede defeat.

A LFS sells their Magnesium mix with the following directions:

160g MgCl2
125g MgSO4
~590ml (20oz) RO water

How would this mix relate to something like Randy's recipe, or the BRS Magnesium mixture in terms of potency? Basically I'm trying to figure how the ratio of the calculators to this mix will end up. Ie. BRS calc says add 100ml of their magnesium mix to dose, the equivalent strength of this would be ____?

Going forward once these couple of mix pouches are done I intend to switch to the 5/2.5-3 cup /gallon methodology, but that's not where we're at right now.

Thanks!

Bmartinez76 · Jun 14, 2018

You’re best bet is to ask your lfs since they likely use it. I use ESV and they have an online calculator which helps with dosing.

Randy Holmes-Farley · Jun 14, 2018

Do you know if those weights are anhydrous or the hydrate? My recipe is about 8 ounces (228 grams) total mag supplement in a gallon of total volume, and used the hydrates. For magnesium salts the water of hydration in the solid crystal can be close to half the total mass.

If they get hot when added to water, they are anhydrous. Otherwise they are almost certainly hydrated, which would also be cheaper to use.

So my expectation is they use the hydrate and their mix is 10 ounces of solids plus 590 mL water and us about 8x more potent than my magnesium mix. [emoji3]

Martin Kuhn · Jun 14, 2018

This mixture / concentration is a bit different to randies recipe, but not too much
(MgCl2 vs MgSO4 ratio is 56% for the LFS recipe, 63% for randies recipe)

Taking this and the different weights into regard, the LFS recipe is 88,7% as potent as Randies

knowing the required amount in ml from randies recipe, you need to divide it by 0,887 and you have the required ml of the LFS recipe.

Randy Holmes-Farley · Jun 14, 2018

Martin Kuhn said:
This mixture / concentration is a bit different to randies recipe, but not too much
(MgCl2 vs MgSO4 ratio is 56% for the LFS recipe, 63% for randies recipe)

Taking this and the different weights into regard, the LFS recipe is 88,7% as potent as Randies

knowing the required amount in ml from randies recipe, you need to divide it by 0,887 and you have the required ml of the LFS recipe.

Note how little water it is in. It’s much more potent.

Martin Kuhn · Jun 14, 2018

Hi Randy
i always prefer to calculcate in "grams" instead of "cups" as beeing more accurate.

From a source that i can't remember at the moment, i took he following information for your Mg-recipe
MgCl2: 1000g/gallon (264,2 gram/Liter)
MgSO4: 600g/gallon (158,5 gram/Liter)
Isn't that correct?

Kyl · Jun 14, 2018

Randy Holmes-Farley said:
Do you know if those weights are anhydrous or the hydrate? My recipe is about 8 ounces (228 grams) total mag supplement in a gallon of total volume, and used the hydrates. For magnesium salts the water of hydration in the solid crystal can be close to half the total mass.

If they get hot when added to water, they are anhydrous. Otherwise they are almost certainly hydrated, which would also be cheaper to use.

So my expectation is they use the hydrate and their mix is 10 ounces of solids plus 590 mL water and us about 8x more potent than my magnesium mix. [emoji3]

They do not warm up when added to water. Their directions are basically add this 20z mixture once you consume a gallon of their DIY part A / B. I'm going with the BRS mix after these two pouches are used up.

Randy Holmes-Farley · Jun 14, 2018

Martin Kuhn said:
Hi Randy
i always prefer to calculcate in "grams" instead of "cups" as beeing more accurate.

From a source that i can't remember at the moment, i took he following information for your Mg-recipe
MgCl2: 1000g/gallon (264,2 gram/Liter)
MgSO4: 600g/gallon (158,5 gram/Liter)
Isn't that correct?

Oops, sorry. I miscalculated my own recipe above. It is 64 ounces (1632 g) total sold hydrates per gallon final volume , and this recipe listed above may be similar potency. I’ve not tried to see what mass or volume of water was needed to attain 1 gallon final volume.

I’m assuming this recipe from the lfs is taken from my recipe.

Kyl · Jun 14, 2018

Randy Holmes-Farley said:
Note how little water it is in. It’s much more potent.

I overlooked this in your replies. If I increased the volume of RODI water to equal about a gallon in the container, diluting the initial mix, it should roughly be around the strength of yours give or take ~10-20%?

Martin Kuhn · Jun 15, 2018

Once
- Randy confirmed that my assumed quantities of his Mg recipe are correct
- Kyl gave the specifications of the LFS recipe, just not knowing if hydrous or anhydrous salts are used
- My potency calculation is re-done
it should be clear now

a) if the recipe uses the typical hydrate versions of the salt what i cleary expect
(MgCl2 x6H2O and MgSO4 x7H2O)
-> the LFS recipe is "a bit more" potent as Randies. 112,8%
-> knowing the required amount in ml from randies recipe, you need to divide it by 1,128 and you have the required ml of the LFS recipe.

b)if the recipe uses anhydrous salts (what i don't expect)
(MgCl2 anhydrous and MgSO4 anhydrous)
-> the LFS recipe is more potent as Randies. 238%
-> knowing the required amount in ml from randies recipe, you need to divide it by 2,38 and you have the required ml of the LFS recipe.

best rgds Martin
PS: Calculations done with flexible 2-part routines from AquaCalculator.

Randy Holmes-Farley · Jun 15, 2018

I’d assume it is the cheaper hydrate and since the amount needed isn’t going to be super accurate anyway, I’d just assume it is the same potency as my diy and use this calculator:

http://reef.diesyst.com/chemcalc/chemcalc.html

Doing so can’t really cause any substantial problems before you run out of that material.