Thank you very much for your comment ^^
I was really worried that the game and the controls wouldn't be intuitive, but reading the comments, I'm reassured on this subject :)
As for the music, the fish is perhaps the one I struggled with the most. I wanted the music to represent the fish when it's small and when it's big. It took me a while to find the right instruments, but thanks to the help of chat (I created the game live), I ended up settling on two instruments to represent it: a muted trumpet for the big fish (which sounds a bit like an old investigative film) and steel drums, which bring out that slightly tropical, imaginary aquatic feel.