I would cut 2 knobs off a cc star every couple of days always made him finish what he had and wait a full day before dropping another
There was also once or twice that after the first cut I lost a star totally I tried feeding it to him frozen he did not eat it at all so now I just drop a whole one in and keep a watch on it if the knobs on it ever go flat get it out its dead and will more than likely be mushy so be careful so far he somehow keeps it alive long enough to eat all of it if you see them out searching the tank he's hungry and finished with it or for some reason it died I don't think they will eat it after it dies ....if you ever smelled one dead I can't blame him lol