mixing magnesium and iron

[wet reefer]

I am currently using 2 dosers. One dual channel for the 2pt
recipe and the other for magnesium. After reading your article on iron I thought I'd dose iron also. Can iron, Iodine and magnesium be mixed together? I am not currently using Iodine but it would be nice to know . This 2nd doser is a single channel.
All are from Kent.
Any links regarding this would be appreciated.

 

[Randy Holmes-Farley]

These are fairly complex questions.

I don't generally recommend that folks add iodine. That said, if you are going to dose iodine, I usually recommend iodide as the form to dose. One of the concerns with putting it into a highly diluted solution for a week or more before dosing is that it may oxidize to iodate. It turns out that iodate is the predominate form in seawater anyway, so that may be OK, but it isn't my preference because it seems that of those organisms that use iodine at all, iodide is often the preferred substrate (although not in all cases).

I do not actually know what will happen to the chelated iron when put into a concentrated magnesium solution. It is possible that the chelating ligand may, to some extent, leave the iron and bind that magnesium. That won't hurt the magnesium because it is such a small amount, but it might decrease the solubility of the iron. You could try it and see if any dark residue seems to precipitate from the mixture over time.

 

[wet reefer]

Understood. I'll give it a try and let you know.
Thank you.

 

[Randy Holmes-Farley]

You're welcome.

These articles may be useful:

Magnesium in Reef Aquaria
http://www.advancedaquarist.com/issues/oct2003/chem.htm

Magnesium and Strontium in Limewater
http://www.advancedaquarist.com/issues/dec2003/chem.htm


First Iron Article: Macroalgae and Dosing Recommendations
http://www.advancedaquarist.com/issues/aug2002/chem.htm

Second Iron Article: Iron: A Look at Organisms Other than Macroalgae
http://www.advancedaquarist.com/issues/oct2002/chem.htm

Iodine in Marine Aquaria: Part I
http://www.advancedaquarist.com/issues/mar2003/chem.htm

Iodine in Reef Tanks 2: Effects on Macroalgae Growth
http://www.advancedaquarist.com/issues/april2003/chem.htm

Good luck.

 

[wet reefer]

Thanks for the links. What I did not see anywhere is the effect of carbon use when dosing iron. I run carbon continously and I've always thought it would remove iron (being a metal). You think this anything to be concerned about? I see no point in dosing the iron if the carbon is going to remove it. I would rather run carbon if I had to choose between the two.

 

[Randy Holmes-Farley]

Carbon will bind many organics, and iron will be bound by organics in seawater, so some is likely exported by carbon, yes. The point is to dose so some is available, even if some is also removed by the carbon. IMO, the merits of carbon and iron dosing outweigh any concerns about conflicts.