Thanks for the email and for using our products! We have actually found that when taking the copper reading using the Multitest: Copper test kit, you want to wait until the blue color reaches its maximum color intensity. This can take anywhere from 1-5 mins. We have since changed the instructions on all newer labels, but older ones will still be in circulation for a while. I hope this clears up any confusion and please let us know if you have any additional questions. Have a great day!