Just reading through the last few comments, I am getting the feeling that I am either really lucky or that someone is doing something wrong.
For starters, I have been having VERY good success with the Fishman Chem CP. I have been dosing it for the better part of two months and split the 1kg bag with my buddy who owns a store. He's reported similar success.
A thing of note; when I read about UV degrading the CP, I figured it prudent to make sure I store the product in a light-protected container. I'm using one of those shoebox tins you'd get from Ikea, sort of like this:
I have a small bag of desiccant in with the powder also.
To date, I've treated six tangs, a school of anthias and a few other assorted fish which were all covered in white dots. My friend has treated countless animals in his system (much to his lamentation, given that he just purchased some 4 gallons worth of copper a few weeks prior) and he swears by it.
Perhaps it would make sense for us to take a look at any secondary causes which would affect the success rate of CP from Fishman Chem? Just throwing it out there for the sake of dialogue.
