question on Seachem Magnesium crystals

[ahullsb]

I usually mix a couple of tablespoons into a plastic container. There are always leftover deposits at the bottom that look like dirt or something. The crystals in the container are more or less clear, but the stuff at the bottom is brown and black. Anyone know what it is and whether it is ok?

[bertoni]

I'd just discard the bottom crud. I'm not sure what it is, and I don't know of a reasonable way to find out.

[Randy Holmes-Farley]

FWIW, this is not my favorite product as it is not ionically balanced. When you finish with it, I'd suggest switching to Kent, ESV, or a DIY.

[The Saltwater Kid]

What is Kent or ESV? I too am using the Seachem Magnesium Builder as I've had pretty good luck with all Seachem products in the past.

[bertoni]

Kent and ESV make magnesium products that contain a lot of magnesium chloride, so the ionic balance is much more similar to seawater than the SeaChem, which is basically just epsom salts.

[Randy Holmes-Farley]

What is Kent or ESV? I too am using the Seachem Magnesium Builder as I've had pretty good luck with all Seachem products in the past.

Most reef additive manufacturers have some good and some not so good products. This Seachem one is one of their less inspired efforts.

[Billybeau1]

Yes, Seachem actually makes a pretty good calcium supplement and a good carbon (Matrix). But for mag, i like Kents Tech-M.

[ChemLife]

As bertoni mentioned, the Seachem magnesium product is a mixture of magnesium sulfate (epsom salts) and sodium chloride (good ol' table salt or rock salt). Most of the product I've seen has the coloured impurity you've mentioned and the mixture of the two salts can readily be seen - look closely and you'll see the two different types of crystals.

ChemLife

[ahullsb]

Originally posted by Randy Holmes-Farley
FWIW, this is not my favorite product as it is not ionically balanced. When you finish with it, I'd suggest switching to Kent, ESV, or a DIY.

I take your word as gospel.

[ahullsb]

Originally posted by ChemLife
As bertoni mentioned, the Seachem magnesium product is a mixture of magnesium sulfate (epsom salts) and sodium chloride (good ol' table salt or rock salt). Most of the product I've seen has the coloured impurity you've mentioned and the mixture of the two salts can readily be seen - look closely and you'll see the two different types of crystals.

ChemLife

Thanks for the info. That makes sense. I've had a tough time raising my magnesium and sustaining it with this product anyway. Actually, now that I'm asking, I was under the impression that once your raised your magnesium initially, that it maintained it's levels fairly well. Is there an obvious reason why mine seems to deplete so quickly?

[Billybeau1]

How often do you do water changes and with what brand salt mix ?

Magnesium does deplete rather slowly under normal conditions.

[bertoni]

There are a lot of organisms in the ocean, and some consume a lot of magnesium, so the consumption rate varies from tank to tank. This article has some data:

http://www.advancedaquarist.com/issues/oct2003/chem.htm