Cody Simpson can add elite swimmer to his already impressive accomplishments, 'cause the 25-year-old just earned a spot on the Australian swim team ... and will compete against some of the world's fastest in the pool at the Commonwealth Games.
Simpson -- musician, actor, and former teen heartthrob -- competed against his fellow countrymates down under on Wednesday ... finishing 3rd in the 100-meter butterfly at the Australian Championships.
And, no shame in finishing behind the first and second place athletes ... both guys are Olympians.