High Zinc- Scraper the cause

[Lostoften]

Recently had an ICP test done, and the zinc level came back elevated. My hands are the only ones in the tank, and I don’t use creams/lotions. I don’t think deodorant is the issue as I rarely enter arm that far into tank, and try and be mindful. I do primarily feed frozen mysis, but prior ICP test was normal for zinc. I don’t see any metal clamps, screws that are in contact with water.

I did start using a metal scraper to clean the glass, that does have some rust on it. This is not stored in the tank, but haven’t been diligent to dry off every time after use. Could this be the cause?

Any way to lower zinc? Or just let normal WC take care of, along with eliminating the source.

Thanks!

 

[Lostoften]

ICP test results and scraper

 

[Randy Holmes-Farley]

I don’t know if that level is high enough to be a problem, but removing sources is a good plan and that scraper might be a source. So might any type of galvanized metal, such as a screw, hose clamp, etc. that you have looked for. I’d stop using that scraper, double check for metal, and then wait for it to decline.

There are several materials that may lower it, such as metasorb or a polyfilter, but they will remove other things too. I’d wait to do that unless there is apparent tank trouble.

 

[Lostoften]

Thanks, I’ve double checked the sump and don’t see any obvious metal. All the clamps are plastic herbie clips.

Posted in the zoa thread, but I’m losing zoa colonies/frags and trying to pinpoint the reason. This was the purpose of the ICP test.

 

[nichthyes]

At what levels do you start to get concerned?

I have some results that I think could be anomalous, bc it's on multiple systems ICP tests, and seemlingly out of nowhere. I'm seeing ICP results as high as 54 and 73 micrograms/L for Zn and over 300 micrograms/L Iodine. Aluminum is also elevated across multiple systems, but not scary.

The results are from two weeks ago, and I asked Triton to redo them, which they did, and said that everything came back the same. Seems a bit weird, but if it's true I'd wanna do something about it. I know it's intended for cupper, but would cuprisorb work for stuff like that?

I have acropora dying in one system (Al: 27 ppb, Zn: 73 ppb, I: 232 ppb), which is why I'm wondering now if those results are real, or anomalous like I suspected previously.

 

[Randy Holmes-Farley]

I don’t think any binder will reduce iodide or iodate, but the zinc and aluminum will be bound to some extent by metasorb, polyfilter, and cuprisorb.

If phosphate is very high, the iodine may be interference as opposed to an actual elevation.

 

[Randy Holmes-Farley]

Thanks, I’ve double checked the sump and don’t see any obvious metal. All the clamps are plastic herbie clips.

Posted in the zoa thread, but I’m losing zoa colonies/frags and trying to pinpoint the reason. This was the purpose of the ICP test.

Ok, then I’d use a binder in case that is the issue.

 

[nichthyes]

At what level would phosphate interfere with Iodine readings?

The fact that multiple tests came back elevated Iodine is weird considering they have diff PO4 levels and all of them were low, but the Zn is what initially concerned me cuz I've never dealt with that before and suspected a metal contaminant of some sort.

Thanks!

 

[Randy Holmes-Farley]

At what level would phosphate interfere with Iodine readings?

The fact that multiple tests came back elevated Iodine is weird considering they have diff PO4 levels and all of them were low, but the Zn is what initially concerned me cuz I've never dealt with that before and suspected a metal contaminant of some sort.

Thanks!

I do not know exactly what the level needs to be for interference with any given company protocols, but Christoph of Oceamo noted it is significant when using icp-OES.

What phosphate levels do you see? If not above 0.2 ppm, I would not worry about it.:

 

[nichthyes]

Last reading on my spectrophotometer was 0.07, which tends to read about 1 order of magnitude HIGHER than the triton. The triton this time came back as 0.138 ppm PO4.

Seems like a whole group of fishy readings, but like I said, they re-tested and said all was normal. Seems fishy

 

[Christoph]

We stop reporting iodine levels in our ICP-OES tests when phosphorus exceeds 150 ppb (~0.45 mg/L phosphate), as interference becomes a significant issue at this concentration.


Notably, this limitation does not apply to ICP-MS, which remains unaffected by phosphate interference. Therefore, iodine can still be accurately determined in phosphate-rich samples using ICP-MS.


All the best,
Christoph

 

[Randy Holmes-Farley]

Thank you, Christoph. :)

 

[nichthyes]

We stop reporting iodine levels in our ICP-OES tests when phosphorus exceeds 150 ppb (~0.45 mg/L phosphate), as interference becomes a significant issue at this concentration.


Notably, this limitation does not apply to ICP-MS, which remains unaffected by phosphate interference. Therefore, iodine can still be accurately determined in phosphate-rich samples using ICP-MS.


All the best,
Christoph

Thanks for the clarification. Our phosphorous is allegedly at 12 ppb, so doubtful this is the issue, but I still don't know why iodine would be at 322 ppb (or Zn at 73 ppb).

I've heard the MS is much better. Would definitely be interested in trying it.

 

[Randy Holmes-Farley]

Thanks for the clarification. Our phosphorous is allegedly at 12 ppb, so doubtful this is the issue, but I still don't know why iodine would be at 322 ppb (or Zn at 73 ppb).

I've heard the MS is much better. Would definitely be interested in trying it.

I would not worry about the iodine. Have you dosed any?

 

[nichthyes]

I would not worry about the iodine. Have you dosed any?

Yeah I've seen higher iodine without negative effects. It's just strange that it would jump the same time as the zinc and aluminum.

I dose a concoction of Iron, manganese, and Iodine (ferric citrate, manganese sulfate, potassium iodine, respectively - can provide amounts if it seems important) to supplement those elements, but the monthly amount to be dosed is based on the iodine reading from the ICP, as the latter two hardly ever budge above zero. However I just noticed manganese also jumped from 0 to 4 ppb from April to May, when previously the highest it's been in 2 years has only ever been 1.0 ppb.

Again, I wonder about the sensitivity of the equipment; anomalies, calibrations, errors... I don't know much about the OES equipment other than it can be finicky, especially for the elements like manganese at 1 -5 ppb. Maybe I'm wrong...