Help! Is my Hanna copper checker broken?

[Lifthvysht]

For some reason every time I check my QT tank with my Hanna checker (copper) it reads higher and higher in numbers? 2 weeks ago it read 0.025 and now it’s reading 0.36. I did a 40% water change and now it’s reading 0.038? Waited 10 min checked it again with a new glass 10ml vile (the extra that comes with the kit) and now it reads 0.55? My fish is very happy, plays in the water flow and eats when I feed. Idk what’s going on here? Kinda upset because I just got this thing about a month ago. Can you caliberate these things or something? Will Hanna replace it or am I outta luck?

 

[Crabs McJones]

@HotRocks any ideas?

 

[HotRocks]

For some reason every time I check my QT tank with my Hanna checker (copper) it reads higher and higher in numbers? 2 weeks ago it read 0.025 and now it’s reading 0.36. I did a 40% water change and now it’s reading 0.038? Waited 10 min checked it again with a new glass 10ml vile (the extra that comes with the kit) and now it reads 0.55? My fish is very happy, plays in the water flow and eats when I feed. Idk what’s going on here? Kinda upset because I just got this thing about a month ago. Can you caliberate these things or something? Will Hanna replace it or am I outta luck?

What type of copper did you dose originally?

Does your QT contain any live rock or sand?

The tester has a tolerance of +/- .05 so any reading at .05ppm or below could still be considered zero.

There is a calibration check kit. To check the calibration of the unit, but there is not a calibration feature. You test the prefilled cuvettes and make sure your reading is accurate.

Were your original readings .025, .038? Or .25, .38? I don't think the tester reads out past 2 decimal points that is why I ask.

 

[Marco S]

How are you washing the cuvettes out? I found my readings getting a bit off when I was washing with regular tap water. Now I wash with RODI water and shake vigorously and wash again, (about three times) and then dry off with a paper towel before and after each reading and they seem a lot more accurate.

 

[Lifthvysht]

@HotRocks i used cupramine to dose with.

A few weeks ago I had the tank at. 0.25 and then I went to test it today and it was wayyy higher than the 0.25. The read was 0.36, I did a phat water change and then it tested even higher. Tested it and the read out said 0.55 I almost certain that’s what I seen?? I hope I’m wrong. I was a bit in a rush when I tested, I hope I just missed a step and my checker is good. Thanks a ton man I feel a bit better with the answers I’m seeing here

 

[Lifthvysht]

@Marco S @HotRocks duuude I totally used tap water like a dummy!!! My glass jars could have been cleaned better I admit. Man I can’t wait to test again. I hope that was the problem.

 

[HotRocks]

@Marco S @HotRocks duuude I totally used tap water like a dummy!!! My glass jars could have been cleaned better I admit. Man I can’t wait to test again. I hope that was the problem.

Keeping clean cuvettes is very important. The tester passes light through the glass to give the reading so a hard water spot or a smudge can definitely skew the reading.