Bubblex

The Bubblex is a suit that Fishtronaut wears in order to fly out of water. Without wearing it, Fishtronaut can't fly to terrestrial areas.

Background
A water gauge meter shows when Fishtronaut is running out of water in several episodes. When the meter is running out of water, Fishtronaut returns to the generating machine that refills his water and tells him his water gauge is full and Fishtronaut is ready to continue his mission.