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www.reef2reef.com
Good morning. I use ICP analysis on the first of every month. It saved my tank last year with an issues no one could figure out.
What was the issue?
. I never have used copper and could not fog out where it would have come from. After an exhaustive search I found a copper screw in the overflow.

After an exhaustive search I found a copper screw in the overflow.
I hope somebody wasn't trying to sabotage your tank. Glad you found it.
Can I ask why? Inaccurate results?In general, I'm not a fan of this company.
No issues with the tank. I use a small bag of Purigen under the filter floss in the second chamber. Thanks for the iodide tip!In general, I'm not a fan of this company.
Are there any apparent issues with the tank? Diatoms?
If we accept the values as accurate...
Aluminum is getting up there. Are you using any white media?
I don't think iodine is typically useful, but you might experiment with dosing iodide.
Every time I read these, iodine is low. Not an expert but iodine does seem to precipitate out fast. Wonder if Randy can weigh in as he has countless times.
Can I ask why? Inaccurate results?
I recently ordered a two pack of these tests haha
www.reef2reef.com
Thanks for the reply.Lack of knowledge on their part when they participated in this forum, and some clearly inaccurate results.
here's a thread where they participated:
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ICP testing
https://www.icp-analysis.com/ Is this a good thing? Based in Colorado. I've never been into much testing but I would do this. $100 for five tests. Comments please.www.reef2reef.com
They said this about alkalinity (which I noted there is "nonsensical crap"):
" I know, I did not mention alkalinity. Alkalinity is not an element. It is a term used when we calculate how stable our pH is, i.e. the buffer. The buffer is calculated from compounds containing Ca and a hydroxide compound (OH). Since OH is a compound, ICP-OES will not perform the calculation of alkalinity."
Thanks for the reply.
Forgive my ignorance, but you know, that’s always confused me. Is alkalinity an element?
| Chemical Species | Relative Contribution To Alkalinity |
|---|---|
| HCO3– (bicarbonate) | 89.8 |
| CO3— (carbonate) | 6.7 |
| B(OH)4– (borate) | 2.9 |
| SiO(OH)3– (silicate) | 0.2 |
| MgOH+ (magnesium monohydroxylate) | 0.1 |
| OH– (hydroxide) | 0.1 |
| HPO4— and PO4— (phosphate) | 0.1 |
I was going to say the same thing...We care about it because it is mostly a measure of bicarbonate that is not easy to test for directly. Here's a discussion about what it actually is from one of my article
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Chemistry and the Aquarium: What is Alkalinity?
Randy provides an overview of alkalinity as to why it's important, how it's measured, and how can it be tested.reefs.com
Chemical Nature of Alkalinity
Based on the definition of total alkalinity given above, it is clear that anything that absorbs protons when the pH is dropped from normal levels to about 4-5 will be counted toward alkalinity. In seawater there are a variety of things that contribute, and in reef tanks the list is even longer. Equation 3 is the defining equation for total alkalinity in normal seawater.
TA = [HCO3–] + 2[CO3--] + [B(OH)4–] + [OH–] + [Si(OH)3O–] + [MgOH+] + [HPO4--] + 2[PO4---] – [H+]
The reason for the 2 in front of the carbonate and phosphate concentrations is that they take up two protons as the pH is dropped down to pH 4. All of the other ions just take up a single proton (except protons themselves which must be subtracted).
The main chemical species that contribute to alkalinity in seawater (and the reason it is useful to reefkeepers) are bicarbonate and carbonate (equations 1 and 2). The table below (from “Chemical Oceanography” by Frank Millero; 1996) shows the contribution to alkalinity from the major contributors in seawater at pH 8. If you start at higher pH, the relative contribution of bicarbonate will go down relative the others.
Other species can also contribute measurably to alkalinity in seawater in certain situations, such as anoxic regions. These would include NH4+ and HS– .
Chemical Species Relative Contribution To Alkalinity HCO3– (bicarbonate) 89.8 CO3— (carbonate) 6.7 B(OH)4– (borate) 2.9 SiO(OH)3– (silicate) 0.2 MgOH+ (magnesium monohydroxylate) 0.1 OH– (hydroxide) 0.1 HPO4— and
PO4— (phosphate)0.1


