In Filtration

In Filtration is a song by Octoplush.

Trivia

 * The song's BPM is the same as of Smallfry's attacks, referencing how you can only use Smallfry in the level where the song plays.

Etymology
The name of this song is a pun off of "Infiltration" and "Filtration", which might refer to the cramped corridors Agent 3 goes through in Alterna Space Center: Entrance. Additionally, there are often filters in aquariums, fitting in with the sea theme of the Splatoon series.