Magnesium test kits

[leslie]

We have two reef tanks with independent water systems. I just tested both using the Seachem test kit and they both measured about 1200 (.05 remaining in the syringe.) This number has never varied for me despite my adding AquaVitro Ions twice a week.

Using the reference sample to compare is not helpful since the reference is supposed to be 1100. What we need is a reference that's 1600 so we can validate our tests.

But how do we do that?

 

[mojo]

Posted to

 

[thewarbrd]

mojo;273785 wrote: You realize you're talking to a GT alum, right? "Certified by UGA" won't end well when the jokes start flying... :lol2:

LOL, no skin off my nose. They pay my mortgage, but still I bust on this place just as much as you could, mostly just to get all the people with football shrines in their office wound up to see how fast they spin.

I'd just personally rather have a Mr. Wizard verify that the home brewed reference solution is true with their fancy equipment if I was going that route. But either way, I should be able to offer up my salifert mg kit to add to the pool of averages, I can provide the reagent batch numbers when I get home to see if they are different than yours.

 

[mojo]

thewarbrd;273825 wrote: I'd just personally rather have a Mr. Wizard verify that the home brewed reference solution is true with their fancy equipment if I was going that route. But either way, I should be able to offer up my salifert mg kit to add to the pool of averages, I can provide the reagent batch numbers when I get home to see if they are different than yours.

Well, Randy Homes-Farley is about the most qualified person I know that can answer the question about the reference solution- he should see it on the Reef Central post.

Yeah - please post your reference numbers here - it'd be interesting to compare.

 

[sailfish]

Mine is very old but the #lot 0451jp7f

Joe

 

[ralph atl]

Leslie;273794 wrote: We have two reef tanks with independent water systems. I just tested both using the Seachem test kit and they both measured about 1200 (.05 remaining in the syringe.) This number has never varied for me despite my adding AquaVitro Ions twice a week.

Using the reference sample to compare is not helpful since the reference is supposed to be 1100. What we need is a reference that's 1600 so we can validate our tests.

But how do we do that?

Chris is working on that!

 

[thewarbrd]

mojo;273828 wrote: Yeah - please post your reference numbers here - it'd be interesting to compare.

Here's the batches off my reagents.

Mg-1: 0908-E
Mg-2: 0908-F
Mg-3: 0808-N
Kit exp: 09-2011

 

[george]

mojo;273785 wrote: Seriously, making up a solution of MgCl in RODI water can't be all that hard - measure by weight, add to the RODI, and you have a known amount. I'm posting on RC today to see if RHF has any insight.

The only problem with this is that if you're using the Magnesium you're using as a supplement, there are variations within that as to how much is moisture and how much is not MgCl. From what I remember from the Seachem presentation on their dry good from a while back (not the one where they introduced the new liquid line), that's a big factor and may make it hard to determine how much of the weight is MgCl.

Of course, you could get lab grade MgCl, but if you don't have a lab grade scale with the isolation chamber and all that, you'll have to mix a mighty big batch of it up to eliminate the measurement errors involved. Otherwise, you're back to the "ballpark" area.

As suggested, calling the test kit manufacturers and asking what their test kits actually test for might give you an idea. One test may be reporting something you don't want or omittiing something you do.

 

[mojo]

Hmm- most other supplements have some reference that can be made fairly easily. Also- I buy my MgCl in 5g buckets, and do have a 100th gram scale. Although given that it takes quarts of the stuff to make a difference in my tank, I'd be surprised if 100th of a gram will make that much difference. And I'm talking the difference of 300ppm between test kits- that's 20% difference at 1400ppm - much more than would be required by a super precise scale or some humidity.

I'm not looking for uber-precision, but I think +/-300ppm is too much variance.