Just a lovely looking game. Great clean visual style and the bubble particle effect and lighting effects are very stylish. I was impressed by the different levels and modes and fluid controls. I loved how the flashlight turns on at the Abyssal zone and how the enemy types began changing.
One point that is hopefully constructive: I found myself a little frustrated at times when a fish hit my fin and it damaged me, maybe the hitbox could be toned down a bit by the fins? I didn't find it too difficult, but it felt like I was being discouraged from making too risky of a maneuver because I wasn't sure exactly what would hit my fins/feet.
Even on Windows, it was a great experience that felt fine with mouse controls, but I would bet it is even better on mobile. Amazing work!