Fishman was one of the bands original members when it formed in 1983, and the band was in fact named after him (he is commonly referred to as Fish). Other than drumming, he also sang back-up vocals and occasionally lead-vocals. He was well-known on tour for his vacuum cleaner solos and his distinctively-patterned dress. Recently, it has been revealed by Anastasio that Fishman is in fact the Wolfman's Brother, a character in a Phish song on the album Hoist.
Fishman also played the drums in a side-project, the band Pork Tornado , with guitarist Dan Archer, saxophonist Joe Moore, keyboardist Phil Abair, and bassist Aaron Hersey.