Selena Gomez and Justin Bieber arrive at the American Music Awards, in Los Angeles, Cali. on Nov. 20, 2011. CREDIT: Valerie Macon/AFP/Getty Images

Justin Bieber's pop star image and R&B inspired songs couldn't be farther from the heady guitar riffs of Phish, but the Vermont-based jam band apparently has a new fan.

Bieber and his girlfriend Selena Gomez, who's also a singer, spent Wednesday night at Phish's Long Beach, California concert - Tie-dye shirt in tow.

According to the Hollywood Reporter, Bieber's guitarist and music director Dan Kanter is a huge Phish fan and had been trying to get Bieber to check out the band for years.

Although Bieber may have gone to the show as a favor to Kanter, reports say it didn't take long for him to get into the music.

Bieber and Gomez were seen dancing with their friends and even brought their own stash of glow sticks to hurl into the air during triumphant moments of the nearly three-hour concert.

Thursday afternoon, Bieber tweeted from his account, "GREAT SHOW last night #withdankanter. @dankanter @phish"

Besides both having diehard fan bases, there's not much Bieber and Phish have in common - but that didn't stop the 18-year-old from going backstage at the set-break to meet the band.

The "Hollywood Reporter" notes that Bieber and Gomez chatted with bassist Mike Gordon and front man Trey Anastasio, in addition to meeting their families.

A picture was released of the couple spending time backstage, before returning to the center light-board to watch the second set.

And as anyone who's been to a Phish show knows, the light-board area is home to legendary lighting wizard Chris Kuroda.

It seems that Bieber's team has been familiar with Kuroda's work for some time. Kuroda has been hired to design the lights for Bieber's upcoming World Tour.

Kanter, Bieber's gutarist, posted a picture on his twitter account of the view standing behind Kuroda during the show.

His tweet reads, "As if there was ever any doubt… Chris Kuroda is the best lighting director ever."

Bieber and his entourage heard almost all 18 songs at the Long Beach Arena show, a venue Phish had never played before.

No word on whether Bieber and Gomez plan to follow the band to San Francisco where they have three shows scheduled this weekend.