HOBBY GRADE TEST KITS CAN OUTPERFORM ICP MEASUREMENTS…REALLY??

[jason2459]

Takes a huge amount in a person with functioning kidneys. i use KCl in place of NaCl as a salt substitute.

Well you know

 

[David S]

One takeaway is that it's probably best to take multiple samples and send them to at least two vendors, who you may consider most reliable and compare results.
To that end, I sent samples to ATI and Fauna Marin. Testing was done on 11/30.
The results are in (see attached).
Really impressed with the consistency of the results. It indicates - to me anyway - a certain degree of reliability.
A few notes:
Fauna Marin indicated 122 ppb of Iodine opposed to 139 ppb by ATI.
While this is not a big difference, I tested a sample for Iodine using Rick Matthew's home made test and it came out to 120 ppb. FM wins.
Disregard the 0 amounts - actually they should be considered as undetectable.
Ati was able to detect Cu and Co, FM didn't.
FM was able to detect Mn and Zn, while Ati couldn't.

 

[Dan_P]

One takeaway is that it's probably best to take multiple samples and send them to at least two vendors, who you may consider most reliable and compare results.
To that end, I sent samples to ATI and Fauna Marin. Testing was done on 11/30.
The results are in (see attached).
Really impressed with the consistency of the results. It indicates - to me anyway - a certain degree of reliability.
A few notes:
Fauna Marin indicated 122 ppb of Iodine opposed to 139 ppb by ATI.
While this is not a big difference, I tested a sample for Iodine using Rick Matthew's home made test and it came out to 120 ppb. FM wins.
Disregard the 0 amounts - actually they should be considered as undetectable.
Ati was able to detect Cu and Co, FM didn't.
FM was able to detect Mn and Zn, while Ati couldn't.

These result differences are small. Typically, they are not although they can be. I wonder if the vendors are a) upping their game to compete with ICP-MS or b) you caught them on a good day

Thanks for sharing the data. I will add it to the vendor comparison database.

 

[David S]

These result differences are small. Typically, they are not although they can be. I wonder if the vendors are a) upping their game to compete with ICP-MS or b) you caught them on a good day

Thanks for sharing the data. I will add it to the vendor comparison database.

Thanks
You know what; my feeling is any day can potentially be a good or bad day, testing wise, depending on where the samples are in the cue.
When I saw these results, I felt my samples were probably tested shortly after the machines were calibrated.

 

[Dan_P]

Thanks
You know what; my feeling is any day can potentially be a good or bad day, testing wise, depending on where the samples are in the cue.
When I saw these results, I felt my samples were probably tested shortly after the machines were calibrated.

You are probably right. There is no getting away from variation. I wish the vendors would provide us with a best guess accuracy and precision rather than us needing to believe the results are good.

 

[jason2459]

I think it's time I do one more round.... to be continued....

 

[Rick Mathew]

Thanks
You know what; my feeling is any day can potentially be a good or bad day, testing wise, depending on where the samples are in the cue.
When I saw these results, I felt my samples were probably tested shortly after the machines were calibrated.

This is probable a good assumption although there could be other factors involved....The issue is when you send in a single test to a selected vendor, are the results you get from a "good day" or "bad day" you have no way of knowing...As Dan stated above, If they would provide a statement of accuracy and precision for each measurement that would be helpful...

 

[David S]

This is probable a good assumption although there could be other factors involved....The issue is when you send in a single test to a selected vendor, are the results you get from a "good day" or "bad day" you have no way of knowing...As Dan stated above, If they would provide a statement of accuracy and precision for each measurement that would be helpful...

The thing I like about sending samples to multiple vendors is if, as in this case, the results are similar, it suggests a certain degree of reliability.
I therefore feel more comfortable dosing or holding back, depending on results.
Also when sending in a sample to a single vendor, I tend to distrust any results that significantly differ from something I test for.
For example, if I test my Nitrate @ between 1 - 5 mg/l and get a single ICP result - say 30 mg/l - I will give credence to MY result, as I've been using an API test for over 30 years.
But, as in this case, there are two independent results indicating my NO3 was 30 mg/l. I'm therefore somewhat convinced that either API changed their formula - or more likely - I got a bad batch.
In retrospect, I had noticed low Nitrate readings using my kit, causing me to dose more NO3 than normal. That should have told me something.
Anyway, I just ordered a Salifert kit which is a distant 2nd for me.

This is probable a good assumption although there could be other factors involved....The issue is when you send in a single test to a selected vendor, are the results you get from a "good day" or "bad day" you have no way of knowing...As Dan stated above, If they would provide a statement of accuracy and precision for each measurement that would be helpful...

This is probable a good assumption although there could be other factors involved....The issue is when you send in a single test to a selected vendor, are the results you get from a "good day" or "bad day" you have no way of knowing...As Dan stated above, If they would provide a statement of accuracy and precision for each measurement that would be helpful...

Understood
and thanks

 

[Rick Mathew]

Thanks
You know what; my feeling is any day can potentially be a good or bad day, testing wise, depending on where the samples are in the cue.
When I saw these results, I felt my samples were probably tested shortly after the machines were calibrated.

David also there is another dilemma I have run into personally when sending the same a sample to two different vendors....That is when they don't agree ....Now which one to believe and take action???

 

[Dan_P]

David also there is another dilemma I have run into personally when sending the same a sample to two different vendors....That is when they don't agree ....Now which one to believe and take action???

There is a popular narrative of using trust in a vendor based on educational pedigree of the staff in lieu of data about testing accuracy to decide which vendor’s data to believe in I provide an alternative narrative.

I will point out that all vendors seem to provide the same result, say within 5-10% of each other, for elements with concentrations greater than 1 ppm. Below 1 ppm, results become erratic. There can be good vendor consensus for an element concentration or there can be very poor consensus. There does not seem to be a pattern to this chaotic condition. Even more frustrating is that in the middle of this vendor consensus chaos, a vendor can show good precision for repeated measurements. Because of this, I am adamant that ICP vendors need to come clean about the accuracy and precision for element concentration measurements they provide. On the other hand, the exact concentration of trace elements may not matter for coral growth. Poorly measured trace element concentrations would then be adequate for the hobby as a litmus test for them.

 

[David S]

David also there is another dilemma I have run into personally when sending the same a sample to two different vendors....That is when they don't agree ....Now which one to believe and take action???

That is the question.
Are we talking about where the two Vendors significantly differ on a few elements or most elements?
If they show a disparity on most, I would check my tests of Calcium, ALK, Mag, Conductivity, Iodine etc and compare their numbers.
Hopefully that would weed out the Vendor with the inaccurate numbers.
If it's only a couple of elements they differ on, I'd go with my gut feeling (how the corals look).
I chose these two Vendors because based on my personal experience of using them (ATI I've used for years and while I've only been using Fauna Marin a relatively short time, I am impressed by them (again gut feeling LOL) and other people's opinion of their service).
I also have kits of several other Vendors, I could have included in this test. I believe I can say with a good degree of confidence, there would have been some great disparities, had any of them been included.
I will be sending in monthly standalone ICP samples, as I have a surplus of tests, and evaluate them the best I can.
However, I do see value in the multiple testing, and will do that every 3 or 4 months.
I'll be more than happy to pass them on.

 

[Rick Mathew]

That is the question.
Are we talking about where the two Vendors significantly differ on a few elements or most elements?
If they show a disparity on most, I would check my tests of Calcium, ALK, Mag, Conductivity, Iodine etc and compare their numbers.
Hopefully that would weed out the Vendor with the inaccurate numbers.
If it's only a couple of elements they differ on, I'd go with my gut feeling (how the corals look).
I chose these two Vendors because based on my personal experience of using them (ATI I've used for years and while I've only been using Fauna Marin a relatively short time, I am impressed by them (again gut feeling LOL) and other people's opinion of their service).
I also have kits of several other Vendors, I could have included in this test. I believe I can say with a good degree of confidence, there would have been some great disparities, had any of them been included.
I will be sending in monthly standalone ICP samples, as I have a surplus of tests, and evaluate them the best I can.
However, I do see value in the multiple testing, and will do that every 3 or 4 months.
I'll be more than happy to pass them on.

Actually I agree totally with Dan's statement...For the most part there is relative agreement, but on some of the trace elements <1ppm there can be differences ....some can be quite large....the difference between dosing the element and making a water change to reduce it it's concentration to do nothing...So essentially different on a few elements ....usually <1ppm levels....Although I have had on some occasions element such as Magnesium, Calcium are different enough to be concerned, but that is the exception and not the rule..

 

[ingchr1]

Actually I agree totally with Dan's statement...For the most part there is relative agreement, but on some of the trace elements <1ppm there can be differences ....some can be quite large....the difference between dosing the element and making a water change to reduce it it's concentration to do nothing...So essentially different on a few elements ....usually <1ppm levels....Although I have had on some occasions element such as Magnesium, Calcium are different enough to be concerned, but that is the exception and not the rule..

A question I have for the <1ppm trace elements. At those levels, are they elements that the average hobbiest needs to be concerned with and trying to adjust? Or just let them be?

 

[Randy Holmes-Farley]

A question I have for the <1ppm trace elements. At those levels, are they elements that the average hobbiest needs to be concerned with and trying to adjust? Or just let them be?

Well, certainly the values are important if one allows them to vary too widely. Not likely within a factor of 2, but trace elements can be too high and are toxic or too low and are not sufficiently bioavailable to benefit the organisms that need them.

 

[ingchr1]

Not sure I worded my question quite right.

If there can be quite large differences in measurements of elements <1PPM, can/should those measurements be used to make decisions on dosing of individual elements? Might one just be better off to just do nothing for those specific elements? Other than maybe a wholesale action like a water change?

 

[Randy Holmes-Farley]

Not sure I worded my question quite right.

If there can be quite large differences in measurements of elements <1PPM, can/should those measurements be used to make decisions on dosing of individual elements? Might one just be better off to just do nothing for those specific elements? Other than maybe a wholesale action like a water change?

That's a far more complicated question, and the answer would be that even if the values were perfectly accurate, there's not much data on what levels of what trace elements are needed in what chemical forms for any given organism we keep (and the answer is not going to be the same for all). Natural levels is a reasonable starting point, but is only a small part of the story.

So with all those many caveats, I'd take ICP as a rough guide, and the real answer can only be determined by trial and error dosing of chemicals (if you think one or more may be too low) or export (if one or more may be too high).

Some methods try to take some of that trial and error aspect away by having done much of that trial and error already (Moonshine, for example). But whether their info applies to the chemical forms of trace elements in your system and the organisms you keep is still somewhat unknown.

IMO, the range of trace element concentrations that are acceptable to a great many corals is quite wide. For some it may be 100x or 1,000x or maybe much more in some cases (very wide range for iron, for example).

 

[David S]

Ok, so I received a Salifert Nitrate test kit to compare against my API kit which was showing an extremely low value of Nitrate versus the results from ATI and Fauna Marin which indicated a Nitrate concentration ~30ppm.
Prior to the test, I had stopped dosing Nitrate from the time I received my ICP results. However, I did dose about 5 ml of Nitrate a few hours prior to receiving the Salifert kit.
I then tested with the API kit and as has been the case with the current kit, it registered virtually no Nitrate.
Then I tried the Salifert and while in the "swirling" process -prior to the 3 minute waiting period - I could see the solution turning pink.
After the waiting period the color result was clearly in the 25ppm range.
At this point, I should point out that I normally prefer the API as I like to keep my Nitrate at 5ppm and at that level I find it easier to read than the Salifert.
I've also been using it for nearly 40 years (going back to freshwater) and this is the first time one of their kits failed.
I should also point out that in getting to a color matching 5 ppm, I obviously overdosed; so I probably was in the 50 - 100 PPM range, in my tank!
Definitely not good.
I'll try to contact API and inquire about the kit's batch number.
Anyway, the irony of all this is I'm in the wrong conversation, because this is a case where the ICP outperformed the Hobby Test kit.

 

[rtparty]

Ok, so I received a Salifert Nitrate test kit to compare against my API kit which was showing an extremely low value of Nitrate versus the results from ATI and Fauna Marin which indicated a Nitrate concentration ~30ppm.
Prior to the test, I had stopped dosing Nitrate from the time I received my ICP results. However, I did dose about 5 ml of Nitrate a few hours prior to receiving the Salifert kit.
I then tested with the API kit and as has been the case with the current kit, it registered virtually no Nitrate.
Then I tried the Salifert and while in the "swirling" process -prior to the 3 minute waiting period - I could see the solution turning pink.
After the waiting period the color result was clearly in the 25ppm range.
At this point, I should point out that I normally prefer the API as I like to keep my Nitrate at 5ppm and at that level I find it easier to read than the Salifert.
I've also been using it for nearly 40 years (going back to freshwater) and this is the first time one of their kits failed.
I should also point out that in getting to a color matching 5 ppm, I obviously overdosed; so I probably was in the 50 - 100 PPM range, in my tank!
Definitely not good.
I'll try to contact API and inquire about the kit's batch number.
Anyway, the irony of all this is I'm in the wrong conversation, because this is a case where the ICP outperformed the Hobby Test kit.

Except, unless I’m mistaken, ICP doesn’t test nitrate. All ICP vendors use a colormetic or titration type kit just like us.

In that case ICP didn’t out perform a hobby kit. The ICP company’s “hobby kit” just out performed your “hobby kit”

 

[MnFish1]

Takes a huge amount in a person with functioning kidneys. i use KCl in place of NaCl as a salt substitute.

Actually - thats not entirely true - depending on what huge means. As a salt substitute - it would be fine with functioning kidneys - but without getting into the intracellular/extracellular buffer system for potassium - which would hijack the thread somewhat - I will just say - you could easily kill someone with a small dose of potassium intravenously. The effects on the heart are nearly instantaneous - not giving the kidneys time to excrete it

 

[MnFish1]

Ok, so I received a Salifert Nitrate test kit to compare against my API kit which was showing an extremely low value of Nitrate versus the results from ATI and Fauna Marin which indicated a Nitrate concentration ~30ppm.
Prior to the test, I had stopped dosing Nitrate from the time I received my ICP results. However, I did dose about 5 ml of Nitrate a few hours prior to receiving the Salifert kit.
I then tested with the API kit and as has been the case with the current kit, it registered virtually no Nitrate.
Then I tried the Salifert and while in the "swirling" process -prior to the 3 minute waiting period - I could see the solution turning pink.
After the waiting period the color result was clearly in the 25ppm range.
At this point, I should point out that I normally prefer the API as I like to keep my Nitrate at 5ppm and at that level I find it easier to read than the Salifert.
I've also been using it for nearly 40 years (going back to freshwater) and this is the first time one of their kits failed.
I should also point out that in getting to a color matching 5 ppm, I obviously overdosed; so I probably was in the 50 - 100 PPM range, in my tank!
Definitely not good.
I'll try to contact API and inquire about the kit's batch number.
Anyway, the irony of all this is I'm in the wrong conversation, because this is a case where the ICP outperformed the Hobby Test kit.

The ICP test kit - is an (hopefully) upgraded hobby test kit - since ICP cannot measure nitrate