For those of you following along, here is a copy of part of a post from my build thread about the QT. Before the QT I was very aware that media like carbon does not play well with copper. That being said I still missed a small but important detail.....
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Well... I did something dumb...
I have been treating my cardinal for well over a month now and have done everything from freshwater dips, ruby reef rally, therapeutic copper, metro, furan-2, kanaplex and have not been able to cure this guy. When I first got my QT set up, I knew that carbon was bad and I needed to remove all filters. I checked the HOB filter and found it was just a filter floss sort of thing, so I left that to hopefully give my bacteria a place to thrive. Today at the frag swap in Nashville,
@Eagle_Steve was kind enough to offer to double check my copper level with his hanna checker, I have just been using the salifert test. Before I met up with him I took another copper measurement and found my copper to be .75 with cupramine. When a sample was put in the Hanna, however, it came back as no copper in the water. This was quite puzzling. Eagle_Steve was kind enough to discuss possibilities with me at length, and he finally pointed out something I did not realize. The filter floss type filter has carbon in the middle of it, when I checked it out before QT I 100% missed that, I apparently didn't feel the copper between the layers. The theory is that the carbon has been absorbing all of my copper. This still does not answer why the salifert test reads the amount that I expect, though. All that to say, I removed the carbon and I am resetting my QT clock. It makes me sad to know that I may have lost my other fish in QT because I missed this detail. It is frustrating to know that I should not have carbon in there, but miss that it was actually integrated into the filter.....