Really cool game and concept! I think the music was a really good fit for the gameplay and style. Player movement was fast and fun, albeit a little floaty at times but I feel like that was part of the challenge. Underwater shader was an interesting and nice touch! As far as criticisms go I think either adding a vent sprite or some targeting arrows or something would be a huge help. It took me a while to figure out that I was just supposed to shoot down at the bubbles because I kept thinking I wasn't going deep enough because I couldn't actually see a vent. I also encountered a game breaking bug where the game crashed when I finally did destroy the vent 😬 Had a lot of fun though regardless!
You can check out my gameplay video playtest here for some more feedback: