Dosage for Copper Power

xzt · Dec 28, 2025

The product label on the Copper Power I purchased states that adding 0.4ml of Copper Power to 1L of water should result in a copper concentration of 2.5ppm. However, based on my repeated tests, I only achieved a reading of 1.9-2.0ppm.There is no sand or filter media in my quarantine tank. I used a Hach UV spectrophotometer to test the copper concentration. Previously, when testing Cupramine, the copper readings were very accurate.

Jay Hemdal · Dec 28, 2025

xzt said:
The product label on the Copper Power I purchased states that adding 0.4ml of Copper Power to 1L of water should result in a copper concentration of 2.5ppm. However, based on my repeated tests, I only achieved a reading of 1.9-2.0ppm.There is no sand or filter media in my quarantine tank. I used a Hach UV spectrophotometer to test the copper concentration. Previously, when testing Cupramine, the copper readings were very accurate.

Yes - I've heard of this dosing issue with Copper Power. I think their label is incorrect. As long as you trust your copper test method, you should use those results to reach a dose of 2.25 ppm.

I presume you're using the Hach Bicinchoninate Method?

vetteguy53081 · Dec 28, 2025

xzt said:
The product label on the Copper Power I purchased states that adding 0.4ml of Copper Power to 1L of water should result in a copper concentration of 2.5ppm. However, based on my repeated tests, I only achieved a reading of 1.9-2.0ppm.There is no sand or filter media in my quarantine tank. I used a Hach UV spectrophotometer to test the copper concentration. Previously, when testing Cupramine, the copper readings were very accurate.

What model test kit are you using to test copper? The model 6000 uses UV beam to analyze chlorine, ammonia, ph, nitrate, calcium levels but does not list copper. The test I know of best in your country would be SERA brand

xzt · Dec 28, 2025

Jay Hemdal said:
Yes - I've heard of this dosing issue with Copper Power. I think their label is incorrect. As long as you trust your copper test method, you should use those results to reach a dose of 2.25 ppm.

I presume you're using the Hach Bicinchoninate Method?

Yes, I've communicated with you in other posts before. Later, I repeated the experiment multiple times and found that following the label instructions does not achieve a copper concentration of 2.5 ppm. I had also discussed the copper concentration of Seachem Cupramine with you previously. After receiving guidance from others, I realized I had only added half the required dosage. When I added the full amount of Cupramine to the test water, the detected copper concentration was 0.51 ppm, which is very close to the officially claimed 0.5 ppm. However, despite multiple experiments with Copper Power, I have been unable to reach the officially stated 2.5 ppm copper concentration.

xzt · Dec 28, 2025

vetteguy53081 said:
What model test kit are you using to test copper? The model 6000 uses UV beam to analyze chlorine, ammonia, ph, nitrate, calcium levels but does not list copper. The test I know of best in your country would be SERA brand

I am using a Hach DR5000 series UV-Vis spectrophotometer. The method employed is the Bicinchoninate Method, with a measurement range of 0.04-5.00 ppm for copper. For the copper test reagent, I chose CuVer® 2 because the CuVer® 1 reagent can be interfered with in seawater. I've noticed that many others commonly opt for Hanna copper test instruments, but I trust Hach more. Therefore, I don't wish to purchase an additional set of equipment.

Jerry Barnes · Dec 28, 2025

I’ve been using CP for years with a Hanna checker and my QT tanks are within .1 of the target. I’m not sure of the accuracy of the Hanna versus what you are using. But my history of using it shows it’s pretty close.

xzt · Dec 28, 2025

Jerry Barnes said:
I’ve been using CP for years with a Hanna checker and my QT tanks are within .1 of the target. I’m not sure of the accuracy of the Hanna versus what you are using. But my history of using it shows it’s pretty close.

It seems I need to borrow a Hana monitoring instrument for comparison.

Jay Hemdal · Dec 29, 2025

xzt said:
It seems I need to borrow a Hana monitoring instrument for comparison.

Personally, I would trust the Hach DR5000 over the Hanna HR checker. They use the same reagents, but their method of reading the sample is different.

The only thing I can wonder is if your DR5000 is out of adjustment? I had one years ago and Hach wanted something like half the price we paid for it to perform a factory certified check and adjustment. I never did that, but was always careful to watch for improper readings - using standards and zero tests to try and confirm our unit was still operating properly. I think my staff "mothballed" it when I retired back in 2021. They now use a DR3900 I think.

xzt · Dec 29, 2025

Jay Hemdal said:
Personally, I would trust the Hach DR5000 over the Hanna HR checker. They use the same reagents, but their method of reading the sample is different.

The only thing I can wonder is if your DR5000 is out of adjustment? I had one years ago and Hach wanted something like half the price we paid for it to perform a factory certified check and adjustment. I never did that, but was always careful to watch for improper readings - using standards and zero tests to try and confirm our unit was still operating properly. I think my staff "mothballed" it when I retired back in 2021. They now use a DR3900 I think.

I rechecked the instrument and found that it was actually the DR3900, but the supplier had provided me with the manual for the DR5000. I consulted the supplier, who stated that the detection reagents, methods, and procedures for both models are the same and would not affect my results. However, I have indeed never calibrated this instrument, as I always assumed that using the reagent kits and calibration curves provided by the manufacturer would eliminate the need for calibration. Yet, when testing Seachem Cupramine, the results were very accurate, which led me to believe it was functioning properly. This instrument has likely been in use for about five years.