No, that can not unfortunately sustain on powder like a mandarin can. Blood worms are not bad if he's eating them. I would also see if you can find live blackworms. Most fish seem to love them. They are not a great long term food option but great when needed, and good for finicky fish like the CBB. Beat up fins will heal. Getting weight on your fish, and getting him eating is your number one goal. I wish you success.Hi, thanks so much for your advice. The copperband unfortunately had his fins torn up in the shop but he’s improving and the lymphocytic is subsiding. I’ve increased my water changes and have reduced nitrates and I can see the cyano is depleting fast which is great. I’ll try to find live clams and I’ve heard that CBB’s can’t resist them. Unfortunately where I live in Australia many things can be difficult to find but I’ll do my best. He’s eating bloodworms and copepods at the moment but that’s really not enough nutrition for him so I’ll see what I can do for him in regard to live food such as clams. Thanks for your help!