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View Full Version : Magnesium Chloride contaminates in Deicer question?


HighlandReefer
10/20/2009, 08:39 PM
I found this article regarding contaminates in mag. chloride used as deicers and its effects on local streams. There was research done on the amount of the deicer it would take to cause problems for different organisms found in streams.

STUDIES OF ENVIRONMENTAL EFFECTS
OF MAGNESIUM CHLORIDE DEICER
IN COLORADO
http://www.dot.state.co.us/publications/PDFFiles/magchlorideenveffects.pdf

On page nine of this report you will find this statement:

"12. The alga genus Selenastrum was tested with 1997-98 deicer for response to magnesium chloride deicer over intervals of 96 hrs. The test showed significant suppression of division rate for the algal cells occurring at deicer concentrations slightly in excess of 0.1%."



O.1% magnesium chloride deicer would translate to how many ppm of this magnesium chloride in our reef tank? More important would be the ppm of magnesium this would amount to if measured in one's tank?

dan223
10/20/2009, 09:23 PM
I believe .1% would equal 1000 ppm. here they show freezgard as being 100% mag hexahydrate http://www.ecgrow.com/index.cfm?event=ViewPage&contentpieceId=3318 That study is quite a bit to read thru and somewhat non conclusive for our purposes as other than their lc sudies their obvservations are uncontrolled

dan223
10/20/2009, 09:54 PM
Another thing about the lc studies, they were done on freshwater animals. Where they measure contaminants they couldnt tell if they came from the deicer or mining or vehicle emmisions. If Im missing something please point it out. I wish I could afford to send a sample in for GC-MS. It would be neat to send in say some peladow and some of the cal chloride that brs was selling and see if they were the same or at least close to as far as purity.

Randy Holmes-Farley
10/21/2009, 05:20 AM
It is somewhat unclear what that means. 0.1% of the de-icer solid itself is much less magnesium. Maybe 100 ppm or so in magnesium, assuming they are referring to the hexahydrate.

Note that the de-icer they talk about (and tested???) uses a rust inhibitor as well as the bulk magnesium chloride. In any case, the list of impurities does point out the concerns with using bulk chemicals of uncertain origin.

Randy Holmes-Farley
10/21/2009, 05:21 AM
It would be neat to send in say some peladow and some of the cal chloride that brs was selling and see if they were the same or at least close to as far as purity.


I did test Dowflake and several hobby brands, but not the BRS material:

Purity of Calcium Chloride
http://www.advancedaquarist.com/issues/mar2004/chem.htm

HighlandReefer
10/21/2009, 07:13 AM
Thanks Randy. :)

I didn't realize there was a rust inhibitor in the mix.

I thought I found some evidence as to why increasing one's mag. level 300-400 ppm might kill algae (Bryopsis) in many hobbyists tanks. ;)

Randy Holmes-Farley
10/21/2009, 07:23 AM
I thought I found some evidence as to why increasing one's mag. level 300-400 ppm might kill algae (Bryopsis) in many hobbyists tanks

It may be.

The reported data may also be the result of ammonia in the mix. That's common in some similar products and I don't recall seeing anything in the article on it.

HighlandReefer
10/21/2009, 07:42 AM
I'm leading toward the heavy metal concentrations in the mixes. The research I have read has found that the combinations of heavy metals have synergistic effects at lower then levels found by each heavy metal alone on killing algae.

I was under the impression that ammonia would enhance algal growth? Not good for the fish though. :)

Randy Holmes-Farley
10/21/2009, 07:54 AM
Algae can consume ammonia, but I do not know what levels become toxic. :)

Randy Holmes-Farley
10/21/2009, 07:55 AM
Algae can consume ammonia, but I do not know what levels become toxic. :)

Randy Holmes-Farley
10/21/2009, 07:56 AM
Algae can consume ammonia, but I do not know what levels become toxic. :)

Randy Holmes-Farley
10/21/2009, 07:57 AM
Algae can consume ammonia, but I do not know what levels become toxic. :)

Randy Holmes-Farley
10/21/2009, 08:01 AM
Wow, gotta love this new software. :D

HighlandReefer
10/21/2009, 08:01 AM
What did you get? Ohh the double post. ;)

Randy Holmes-Farley
10/21/2009, 08:07 AM
It kept telling me I had to wait, but when I refreshed the thread, no posts where there. So I kept posting until something showed up. :D

HighlandReefer
10/21/2009, 08:16 AM
It seems to take forever. One time it stated and corrected me when I did a doulble post. :lol: