hi scottbec,
feed him biger items, my 40 cm maccies are eating 2x 1 week old rats, your snake should be on at least weaner mice now at that size, up to you how often you feed, but the fact that he is looking for food after 3 days should be enough to tell you he needs some more food,
i feed all my snakes between 5 to 8 days, depending on other jobs i have, most get a few items, my bhp's are eating 3 x 4 week old rats at a time, they are only about 10 months old, my yearling jungle will eat adult mice, about 4 at a time and be looking for more in a weeks time,
a lot of the time will depend on the snake as to how active it is, but thats just my opinion,
cheers,
steve.......