ICP Results - Feedback?

[tmRoth]

I received results from my first ATI ICP test, done out of curiosity rather than any particular problems other than an ongoing bubble algae issue that is coming under control. I'd be interested in feedback from those more experienced than I am with these tests.

Results are here: https://lab.atiaquaristik.com/publicAnalysis/230678. They should be public but I can post a screenshot if needed, and I attached a PDF of the results.

My 90-gallon tank is around 15 years old and I'm using Reef Crystals, with a 10 gallon (roughly 10%) water change every week or two. I'm doing bi-weekly dosing of Reef Builder, Reef Calcium, Reef Trace, and Reef Plus, with Red Sea magnesium as needed.

1. Asking for general opinions/advice - do any of the results jump out at anyone as a real problem?

2. Phosphate is 0.02 by ICP, 0.12 by Hanna ULR (tested at the same time I collected the ICP sample). The Hanna reading has been consistent at 0.12-0.15 over 5 weekly tests. I'm wondering whether I should throw out the Hanna tester? Or order the $15 calibration standards? I feed heavily but I have a lot of chaeto and have been using PhosGuard to keep that Hanna number from going any higher.

3. Iodine (183.9 ug/l) is 3x the "ideal value" of 61.88. Is this a problem? For a short time (a month, maybe), I was dosing Brightwell Iodion at half or less of their recommended dosing, but stopped a couple of months ago when I learned how inaccurate home iodine tests were. Is there any other potential ongoing source of iodine that could be contributing to this high value?

4. Copper is 3.30 ug/l - any issue with the copper level? I have a healthy population of snails and my emerald crabs are doing well, so I'm assuming this level isn't hazardous. I even had a bunch of baby snails sitting on a rock recently.

5. RODI water results were all non-detect except for nitrate at 2.0 mg/l. Salifert shows zero. I read in another thread that ICP isn't very accurate for nitrate? Is that correct, and could this be a false reading? In any case, my nitrates in the DT are good by both ICP and Salifert.

Also, just curious whether people use ICP as a sort of calibration of the other tests. For example, salinity is 33.61 with ATI, but it was 35 with my refractometer (which is calibrated to 35 ppt using Randy's recipe for a calibration solution). Would it make sense use a refractometer reading between 36 & 37 as being representative of a "true" 35 ppt?

Interesting (to me) observations: Magnesium testing was pretty close (1398 ICP vs. 1305 by Salifert), and so was nitrate (8.45 by ICP vs. 5 to 10 by Salifert. Alkalinity is 7.85 by ICP, 8.4 by Hanna; the Hanna is reading 7% higher; they claim a +/-5% accuracy, so this isn't too far off.

Thanks for any feedback!

 

[Randy Holmes-Farley]

Assuming the values are accurate, here are my comments...

Salinity is a bit low. I'd raise it.
Potassium is very low. I'd add it.
Bromide and boron are high, though I wouldn't do anything about that except not add more (boron from a buffer?)
Iodine is high. If you are adding it, add less. Otherwise, ignore it.
You might benefit from certain trace elements, such as manganese, vanadium, iron (?)
Aluminum is elevated, possibly from white media of some sort, but probably isn't high enough to be a problem

 

[tmRoth]

Assuming the values are accurate, here are my comments...

Salinity is a bit low. I'd raise it.
Potassium is very low. I'd add it.
Bromide and boron are high, though I wouldn't do anything about that except not add more (boron from a buffer?)
Iodine is high. If you are adding it, add less. Otherwise, ignore it.
You might benefit from certain trace elements, such as manganese, vanadium, iron (?)
Aluminum is elevated, possibly from white media of some sort, but probably isn't high enough to be a problem

Thanks, Randy! After posting my original message, I realized it was way too wordy - sorry.

I found your instructions for potassium dosing in another post. and will look into the other trace elements as well (both the high ones and the low ones). I dosed iodine for a short time but quit doing so several weeks ago.

"Assuming the values are accurate" is my concern, especially for salinity because I checked my refractometer using your recipe for a standards solution and it was spot-on for the 35 ppt, and reads zero for RODI, so it seems to be properly calibrated.

 

[Salty_Northerner]

I'm no expert by any means but I do a lot of research and I try and weed out the truth from the nonsense. Here's my comments, Even BRS say that an ICP test is not truly accurate. It'll show you pretty much a snapshot of what's going on but it's kind of like a hobby grade test that goes beyond what us normal people have for testing if that makes any sense. I don't know, I do trust Mr Randy tenfold over what a lot of others say is true.

I just thought I would share what I ran across this evening.

 

[tmRoth]

I'm no expert by any means but I do a lot of research and I try and weed out the truth from the nonsense. Here's my comments, Even BRS say that an ICP test is not truly accurate. It'll show you pretty much a snapshot of what's going on but it's kind of like a hobby grade test that goes beyond what us normal people have for testing if that makes any sense. I don't know, I do trust Mr Randy tenfold over what a lot of others say is true.

I just thought I would share what I ran across this evening.

I don't put 100% faith in the testing, either. I've been working in the environmental field (hazardous waste, groundwater contamination, etc.) for over 30 years. When we collect samples we do a certain percentage of samples as field splits (collect a double-size sample and split it into two samples for individual testing) and field duplicates (sample the same location twice), and there can be fairly substantial differences in analytical results between the originals and the splits or duplicates.

I don't want to spend the money, but it would be interesting to send two samples of the same tank water, collected at the same time, to see how the results compare.

 

[miller75]

I'm wondering whether I should throw out the Hanna tester? Or order the $15 calibration standards?

You cant calibrate the Hanna Phosphate checker the standards just tell you if its within specification, if its not you just have to replace it

 

[Randy Holmes-Farley]

You cant calibrate the Hanna Phosphate checker the standards just tell you if its within specification, if its not you just have to replace it

Worse, it doesn’t test the reagents or procedures used.

 

[rtparty]

I have found ATI salinity to always come back around 1ppt lower than what I test no matter how well I calibrate my refractometers. I question their salinity readings at this point and shoot for 34 on ATI salinity.

Potassium defintely needs to be dosed. I use Brightwell for this. You Hanna might read higher PO4 because of slightly elevated silica. I am not sure how high silica needs to be to throw off the Hanna checker but I would trust ATI here. I don't like or ever use any type of PO4 removal media. I find it causes more issues than it ever solves.

 

[Tjm23slo]

Assuming the values are accurate, here are my comments...

Bromide and boron are high, though I wouldn't do anything about that except not add more (boron from a buffer?)

At what level do you consider Bromide too high. If 65-85 are elevated, above is high, what level is too high? I saw you were over 100 in a Triton ICP test, and you didn’t seem concerned. is there a level that might put you to take an action like a larger WC?

 

[Randy Holmes-Farley]

At what level do you consider Bromide too high. If 65-85 are elevated, above is high, what level is too high? I saw you were over 100 in a Triton ICP test, and you didn’t seem concerned. is there a level that might put you to take an action like a larger WC?

I am not sure what level of bromide becomes a problem, but it generally is not particularly toxic. Unless it was over 200 ppm, or the tank was suffering in some unexpected way, I probably would do nothing.