I had a copperband successfully for 2 years. It ate frozen food from my hand everyday. He was angry at me when he couldn't see out the glass due to algae. He'd swim by nodding his head at me saying hey! the glass needs cleaning.
He picked at the rocks eating pods constantly! That was his nighttime hobby was searching out pods! Due to the beak, they can only eat so much, to keep them healthy, they must constantly eat. I made my own frozen food full of nutrients and he would gobble up that food like it was candy. Sadly 2 years almost to the day I found him wrapped around one of my MP40s. The reason, I suspect is I had one of my fish get big over a year and that fish became an aggressive eater, pushing all other fish out of the way when I fed. I suspect when the agressiveness of other fish elevated the copperband gave up. They're very sensitive fish! I don't know if I'd add them first. They don't fair well with competition and agressiveness. :(