Very fun chill game to relax to. I really like how you took the prompt and ran with an idle experience. Since you mentioned a post jam version of this just some quick suggestions:
The gameplay loop feels a tad unrewarding as an actual game, it's more of an interactive screensaver. In a full version I would love to see the functionality to idly earn money or points and then spend them on new decorations for your fish environment and possibly even teach them new patterns/tricks for even more sincronized satisfaction. Bonus points if you can unlock things that the fish can actually interact with. Overall very satisfying to watcha and has potential to be a very cool idle game.