Quote Originally Posted by newcan1 View Post
I also have some CD4 from Zone V, that I bought in 1987! It is a bit on the dark side, so I have it put aside for emergencies, but it still works. It may be about 10% or so less effective than the fresh stuff I am using. It's amazing how long dry chemistry keeps.
Thanks, newcan1. I asked myself many times in the past 10 years if I should toss my Hydroxylamine Sulfate and CD-4. Glad that I did not actually let go the stuff. Never thought I would ever use it. Based on your message I probably need to increase the dosage of CD-4 to about 5.5 grams per liter of water. Hope to get to try it in the next few days.