Copper in the reef

[Ricardovtav]

Hello, has anyone tested the hn copper test by hanna in the main aquarium? I used it on mine and for between 0.15 and 0.24, I also tested it right after preparing the aquaforest salt and the result was 0.16, is this normal?

 

[Randy Holmes-Farley]

It is “normal” in that it is a commonly attained result, but it is almost certainly inaccurate unless you are medicating the tank. That device is not useful for measuring copper in a normal reef tank. Folks have verified the inaccuracy by checking with an icp test and finding no copper.