Science Buddies: "Ask an Expert"

I am working on a project where I am using copper sulfate. I have made a stock solution with 1 gram of copper in 2 liters of water to get 500 ppm of copper. I want to dose 3 tanks with 6 liters of water with a lower dosage from my stock. I have tried 72 drops but when I took the water to be tested using the Hach Company Porphyrin method it read too high. I have to lower my dosage. I was told to use a syringe instead, but I am unsure how much will be enough. The machine measure up to 200 micrograms per liter. If I lower it to .1 ppm would that be ok to register on the machine. How much should I use in a syringe that using ML measurements?

Hi,

Yes, 0.1 ppm should register on the machine, since 200 micrograms per liter = 0.2 ppm. To dose each tank to 0.1 ppm of copper sulfate, add 1.2 mL of your stock solution to each tank.

Hope this helped,
Allison

Thank you so much for your help!