Like most large fish they'll get anything. Good quality pellet food or fresh raw shrimp peices. I've never weined one off of live though. Can't help there.
piss easy to wean. the only reason mine got on pllets was coz the petshop couldnt get any feeders in. after 2-3 dayz there appetite took over and they ate anything near them, even ate algae wafers in tended for my plecs!!!