High P with ICP Test

[A3LXK]

#I did a Ati MS ICP test which came back with a very high P and Po4 168 ug/l / 52 mg/l. When I test my Po4 with my Hanna Hi-736 the result is 0.09 ppm.

I have checked the Hanna first with a reference solution of 0.12 ppm. The result was spot on 0.12 ppm.

What to believe? Does the ICP went wrong somewhere?

Regards,
Adri

 

[BioChris]

You mentioned your PO4 according to the ICP test was 52 ug/L which converts to 0.052 ppm. You tested with Hanna at 0.09 ppm, what’s the issue?

 

[A3LXK]

You mentioned your PO4 according to the ICP test was 52 ug/L which converts to 0.052 ppm. You tested with Hanna at 0.09 ppm, what’s the issue?

Oops, I made a typo. It is 52 mg/l

 

[BryanM]

Oops, I made a typo. It is 52 mg/l

I would contact ATI. 52 ppm Phos is massively high, and seems to be a testing error.

 

[Randy Holmes-Farley Verified Community Expert]

it’s 0.52 ppm. Not that high

 

[Randy Holmes-Farley Verified Community Expert]

Icp and Hanna do not detect the same chemicals. Both may be accurate, or one or both may be wrong.

 

[A3LXK]

Icp and Hanna do not detect the same chemicals. Both may be accurate, or one or both may be wrong.

What if ICP is right, can it cause trouble?

 

[BryanM]

What if ICP is right, can it cause trouble?

I never intentionally ran my tank at .9+, but there is no denying it happened.

Did it possibly contribute to some coral loss, likely, but not known for sure.

It is currently at .54 and things are thriving. Should you take steps to lower it slowly, likely yes. But .54 is not a 3-alarm fire.

 

[Randy Holmes-Farley Verified Community Expert]

What if ICP is right, can it cause trouble?

Not really. Some great tanks have twice as much (1 ppm).

 

[Randy Holmes-Farley Verified Community Expert]

This has more:

https://www.reef2reef.com/ams/randy’s-thoughts-on-nutrient-target-ranges.1087/

 

[Lasse]

#I did a Ati MS ICP test which came back with a very high P and Po4 168 ug/l / 52 mg/l. When I test my Po4 with my Hanna Hi-736 the result is 0.09 ppm.

I have checked the Hanna first with a reference solution of 0.12 ppm. The result was spot on 0.12 ppm.

What to believe? Does the ICP went wrong somewhere?

Regards,
Adri

I´m a little confused - how is the PO4-P and PO4 measure done at ATI - a ICP-MS is not reliable to analyse P according to @Christoph Oceamo never report P in their ICP-MS tests only PO4 that is measured by spectrophotometry.

Sincerely Lassse

 

[EnterName]

#I did a Ati MS ICP test which came back with a very high P and Po4 168 ug/l / 52 mg/l. When I test my Po4 with my Hanna Hi-736 the result is 0.09 ppm.

I have checked the Hanna first with a reference solution of 0.12 ppm. The result was spot on 0.12 ppm.

What to believe? Does the ICP went wrong somewhere?

Regards,
Adri

I´m a little confused - how is the PO4-P and PO4 measure done at ATI - a ICP-MS is not reliable to analyse P according to @Christoph Oceamo never report P in their ICP-MS tests only PO4 that is measured by spectrophotometry.

Sincerely Lassse

ATI does not use spectrophotometry as far as I know. They simply measure P using ICP and multiply it by approx. 3.066 to go from P to PO₄ assuming all found phosphorus is phosphate.