proper use of nitrate test
I have the "saltwater master liquid test kit" from Aquarium Pharmaceuticals, Inc..
Regarding the nitrate test: First I add 10 drops from bottle #1, then shake bottle #2 for 30 seconds, then add 10 drops from bottle #2, then shake the sample for 60 seconds, then wait 5 minutes and read the result.
"Shake" is the word I am using -- I do not have the original instructions, only the picture instructions on the reverse of each test card. The picture instructions show the vial or bottle with arrows around it to indicate what I interpret as either shaking or inverting.
My question is: do I vigorously shake the sample, or merely invert it repeatedly for the designated time? The more vigorously I shake it, the higher the result.
Sorry for the long post.