Dosed Cupramine too Low

[greetl01]

Tried to lower from .59 to .5 and and it went down to .47. I did a search before making this post and read that Cupramine is still therapeutic at .35. I just want to confirm that I’m ok bc I can not seem to get it exact for the life of me. I even mixed up 4 gallons for water changes and the closest I could get it is .52. My scale broke and all I have is pipettes and I’m about ready to call it . Used up 6 reagents and still have to test again.

 

[Jay Hemdal Verified Community Expert]

So - I have a sneaking suspicion that you are using a Hanna checker, right? I just bought my first one a few months ago, I normally use a lab spectrophotometer, but I wanted to see how well these work. Pretty cool that they give two decimal points on the readout, but I am NOT confident that they read with that precision. I've run some testing on spiked standards and got some results I can only explain by the meter giving readings that are plus or minus 0.1 mg/l That means that the second decimal place, while looking impressive, may not be based on real world measurements. I would round that off - .35 = .40, .47 = .50 etc.

Jay

 

[greetl01]

So - I have a sneaking suspicion that you are using a Hanna checker, right? I just bought my first one a few months ago, I normally use a lab spectrophotometer, but I wanted to see how well these work. Pretty cool that they give two decimal points on the readout, but I am NOT confident that they read with that precision. I've run some testing on spiked standards and got some results I can only explain by the meter giving readings that are plus or minus 0.1 mg/l That means that the second decimal place, while looking impressive, may not be based on real world measurements. I would round that off - .35 = .40, .47 = .50 etc.

Jay

Yes, I am smh great. I just added more saltwater. I’m done