Damn. A very interesting entry!
This might be the most visually appealing game of the jam yet, you're only combining primitive shapes together. Impressive. I'll have to note it down in my book. The particle system and the music are very simple yet, they are very effective at conveying the fact that you're underwater.
This game brings me Agar.io flashbacks. What would you add to this game if you had 3 days instead of 3h to work on it?