Here's a video of Willie my Copperband butterfly back in 2013:
2013 youtube video of my 40B reeftank
I actually acquired him 2 years before that, and by 2013, became tame enough to eat from my hands, as you can see in the video. Sorry the youtube video resolution is low, this was back in 2013!
He thrived in the 40 gallon tank until 2019, just last year when he started going blind. I think it was old age, he was larger than a juvenile when I acquired him to begin with, + 8 years in my 40B tank.
Even blind, if i took some blackworms in my fingers and put it in front of his face he would devour the live blackworms. In fact, I think the key to my success with Willie, was the live blackworms. Wriggling around the water as they sink, and wriggling around 10 more seconds on the liverock when they land, I think any healthy butterfly that is not stressed, would devour them. Eventually, this led to Willie rising to the water whenever I came, and next whenever I dipped my hands in the water he would nip at my fingers hoping for blackworms.
I was able to ween him off to frozen mysis shrimp but I could tell he wasn't as enthusiastic about it as the live blackworms.
I miss him. So far, I've transplanted my tank into a RedSea Reefer 350 just last year, but because of some new additions to the tank, such as a mimosa (hybrid) tridacna clam and a maxima clam, I would rather not risk the clams on another Copperband. Even though I would love to acquire a new Copperband and know that if I get a healthy specimen, starting them off blackworms will help my chances of success.
What do you think, should I risk it with my 2 clams?