Cool game! Love the relaxing atmosphere and the beautiful underwater exploration. And it was surprisingly challenging. I missed some of the early species and swam around in circles at the bottom for a long time. But I enjoyed the visuals while down there.
I think this game doesn't fit the limitation of the game jam though. There doesn't seem to be any system of health at all. What if the player character needed oxygen? The player wants to explore these beautiful underwater biomes and meet all the tiny critters but needs to surface for air, or after daring to venture to the bottom of the pond, can collect air bubbles from a creature or vent. This seems a natural fit for your game and the jam limitation.