Hanna Copper Checker HI702 low-end accuracy

[martin.a]

Hi Guys, HI702 just showed 0.05 ppm copper in my display tank. I know that 0 ppm is within the instrument's accuracy (+/-0.05 ppm +/-5% of reading). But, as I am running copper quarantine tank nearby (Copper Power), I started worrying that I messed something up.

I found @Randy Holmes-Farley posts saying that HI702 should not be trusted at lower end. I just wanted to confirm that indeed that is the consensus opinion and I don't have 600 L of copper contaminated water.

 

[Randy Holmes-Farley Verified Community Expert]

This device had demonstrated itself unsuitable for verifying low levels of copper appropriate for an operating reef tank (regardless of claims by Hanna). . A number of folks see copper with it when no elevated copper exists by ICP.

I recommend it ONLY for medication levels.

 

[Randy Holmes-Farley Verified Community Expert]

Example where the Hanna sees 27 times as much copper as duplicate high end icp tests (by Oceamo):

https://www.reef2reef.com/threads/icp-says-i-have-copper.1138746/

 

[EnterName]

Example where the Hanna sees 27 times as much copper as duplicate high end icp tests (by Oceamo):

https://www.reef2reef.com/threads/icp-says-i-have-copper.1138746/

I have never checked how copper tests work but do you know what may Interfere with the test at low levels?

 

[Randy Holmes-Farley Verified Community Expert]

I have never checked how copper tests work but do you know what may Interfere with the test at low levels?

No, I don't know what might be causing this issue. Hanna uses a standard bicinchoninate method, but it is not usually pushed to the low levels of interest here.

Hach discusses it here:

https://www.support.hach.com/myhach/s/article/KA-en-US-TE12977-1030107?language=en_US

 

[EnterName]

I have never checked how copper tests work but do you know what may Interfere with the test at low levels?

No, I don't know what might be causing this issue. Hanna uses a standard bicinchoninate method, but it is not usually pushed to the low levels of interest here.

Hach discusses it here:

https://www.support.hach.com/myhach/s/article/KA-en-US-TE12977-1030107?language=en_US

Thank you very much!

Sounds like water hardness may interfere based on what approach they use for the bicinchoninate method. CuVer1 from hach would have water hardness interfere , CuVer2 is more resistant...

Either way, the name of the method alone gives me stuff to research. Thanks again!