Google Loon or whatever they called the stratospheric balloons carrying solar powered cell/wifi base stations that made their way around the earth with the Jets

Google Loon or whatever they called the stratospheric balloons carrying solar powered cell/wifi base stations that made their way around the earth with the Jetstream or w/e used a bladder in the balloon that was inflated/deflated with ambient air. Similar to a ship taking/releasing ballast water in ballast tanks.