Lost my Copper band

Well, week three with the new scrubber I made, thanks for all the help there. yesterday i cleaned my screen for the third time .A very nasty brown-red .anyway it seems my corals have really started to grow and start to open up. So i did a Nitrate test ! My nitrates went from 20ppm to 2 ppm in one week !!!!!!! Today i got home to a very bad lookin Copper band . I think the change was to much for him . I am glad for my water but sad for my copper band he did not make it . I will not try anouther one untill i think i am reddy . :(
Anyways this sight is awwwwsome thank you for all the great info! My 125 thanks you too.

I don't think the fish is related to the scrubber. If anything, lower nitrates only help a fish. If it had been several months after your scrubber started, and if your copperband was starting to look skinny, I'd have said that the reduced nuisance algae in the display may have given the fish less creatures to eat. But even then, tiny tubeworms usually start popping up with a scrubber, and this would be more food for him.