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Is Magnesium powder you use in a reef tank the same as magnesium powder we use for planted tanks?

I think it's not just one ingredient in there, if I remember correctly. They were very quiet when I asked the rep and they just said a blend of things. Few aquatic companies like to divulge their "secret family recipes".
 
I think it's not just one ingredient in there, if I remember correctly. They were very quiet when I asked the rep and they just said a blend of things. Few aquatic companies like to divulge their "secret family recipes".
It looks and feels different to the mag i bought for ferts but i was hoping i could use it as very rarely use it in my reef so just sat there really, makes you wonder what we are acyually putting in our tanks.
 
Hi all,
red sea magnesium powder for my reef tank, can i use it for my planted tank or is it totally different?
Its a really fine, very white powder, Not as powdery as flour but a similar consistency
I'm going to guess it is mainly magnesium carbonate (MgCO3). If it is it will have a very low solubility, while magnesium sulphate (MgSO4.7H2O) or magnesium chloride (MgCl2) will be fairly soluble.

cheers Darrel
 
Hi all,


I'm going to guess it is mainly magnesium carbonate (MgCO3). If it is it will have a very low solubility, while magnesium sulphate (MgSO4.7H2O) or magnesium chloride (MgCl2) will be fairly soluble.

cheers Darrel
It dissolves quite quickly and easy just by shaking the bottle
 
Hi all,

That useful, so either magnesium chloride (MgCl2) or a mix of MgCl2 and MgSO4.7H20. In that case you could use it, although you wouldn't know exactly how much magnesium you had added.

cheers Darrel
Thanks, not much point using it if i dont know how much magnesium ive added.
 
Hi all,
Thanks, not much point using it if i dont know how much magnesium ive added.
I couldn't find what it contains, but I have managed to find <"dosing instructions">. You could work out what salt(s) it contains from those values

"1ml will raise the Mg level of 100 liters (25 gal) by 1ppm. Powder supplement: 1g will raise the Mg level of 100 liters (25 gal) by 1.34ppm"

cheers Darrel
 
Hi all,

I couldn't find what it contains, but I have managed to find <"dosing instructions">. You could work out what salt(s) it contains from those values

"1ml will raise the Mg level of 100 liters (25 gal) by 1ppm. Powder supplement: 1g will raise the Mg level of 100 liters (25 gal) by 1.34ppm"

cheers Darrel
Thats what i use in my reef tank so is it the same ppm raise for a freshwater? I know there are lots of things you can use in a reef tank but not in a freshwater.
 
Hi all,
so is it the same ppm raise for a freshwater?
Yes, it just depends on the percentage of magnesium in a compound. Both magnesium salts mention are usually <"hydrated">.

"Epsom salts" magnesium sulphate heptahydrate (MgSO4.7H2O) is ~10% Mg and MgCl2.6H2O has a RMM of 203.3, magnesium has a RAM of 24.3, and 24.3/203.3 ~ 8% Magnesium, so it doesn't really matter which compound it is, they both have similar magnesium contents.

If you look at the "Red Sea" details, there is something a little strange.
1g will raise the Mg level of 100 liters (25 gal) by 1.34ppm
One gram is 1000 milligrams (10^-3) and milligrams per litre are equivalent to ppm (10^-6). A litre of water weighs 1000 grams, so 1 g of magnesium sulphate heptahydrate in 100 litres of water would only give you 1 ppm magnesium and you would need a less hydrated form of one (or both salts) to get to 1.34 ppm from a 1 gram addition to 100 litres.

cheers Darrel
 
Hi all,
they say 1 gram in 25 gallon will add 1.34 ppm Mg, this dose matches with MgCl2*6H2O, the exact dose is 1.0607 gram. its not MgSO4*7H2O that they are using because that would have been 1.286 gram. hope this helps
That is the answer.

It would help if I actually do the simple bit of maths and end up with the right value for 24.3/203.3 .

Cheers Darrel
 
I also found this below:

"Red Sea Foundation C is a component of the Red Sea Reef Foundation program for healthy and vibrant corals. Red Sea Foundation C is a blend of magnesium salts in the proper ratio for seawater. Red Sea's dry magnesium additive adds magnesium in proper chloride/sulfate proportions when used with the Red Sea Reef Foundation System."

they must be adding some part Mgcl and some part MgSo4, I would say very little MgSo4 and lot more MgCl judging by their description of making stock solution. $30 that's way too much

looking at their Foundation program, it seems like they very well could be using both MgCl2*6H2O and MgSO4*7H2O, for Calcium its almost always they would use CaCl. but either way their "Foundation System" is nothing but a simple salts which can be easily obtained to make "Several Foundation System"

Red Sea Reef Foundation System:

Package Contains:


250mL Reef Foundation A (Ca,Sr)

250mL Reef Foundation B (Alk)

250mL Reef Foundation C (Mg)

Reef Foundation A: 1 mL will raise the Calcium level of 25 gallons by 2 ppm.

Reef Foundation B: 1 mL will raise the alkalinity of 25 gallons by 0.036 meq/l (0.1dKH).

Reef Foundation C: 1 mL will raise the Magnesium level of 25 gallons by 1 ppm.
 
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they say 1 gram in 25 gallon will add 1.34 ppm Mg, this dose matches with MgCl2*6H2O, the exact dose is 1.0607 gram. its not MgSO4*7H2O that they are using because that would have been 1.286 gram.
1648420652575.png

1648420708727.png


Best check your maths ;)

I also used 'what if analysis' 'goal seek' in excel and no mix of MgCl2.6H2O and MgSO4.7H2O will give 1.34 ppm Mg in 1.0gram mass. Which is obvious from the pics above ( did the 'what if analysis' 'goal seek' first)

They must be using some anhydrous MgCL2 which would help hot the 1.34 ppm Mg for 1.0gram in 100 litres or it could be just some Magnesium Chloride Flakes in their mix from the read sea
1648421750421.png

Not sure how hydrophilic/stable anhydrous MgCL2 for storing is 😬 am sure @X3NiTH could enlighten us
But we don't need to hit the magic 1.0gram to match the product as if using MgCl2.6H2O (which I am sure is more stable for storing) as all we are adding is a little extra H2O in mass when using MgCl2.6H2O
We don't have anhydrous MgCL2 added to the IFC calculator. But if your keen to find the answer I could add it to my version and find the Cl :SO4 ratio then use that and 'what if analysis' to get the masses of MgCl2.6H2O and MgSO4.7H2O to yield of clone to get 1.34 ppm Mg per 100 litres yielding the same Cl :SO4 ratio

second thoughts they could also be using anhydrous magnesium sulphate -which is a desiccant - we have that on the IFC
1648422825051.png

So without the [Cl] and [SO4] of the product for 1.0 gram per 100litres we cant do an exact clone as it could be a mix of all four salts
 
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