Overall I think this is actually a really fun concept! I came into this not very sure what to expect but had fun trying to navigate and grow the fish. I think there's a few things that can be done to make it feel more complete and take it even further so I wanted to add those here:

Sound design: I think the music actually fits quite nicely with the game but I will say that the sound on death didn't feel like it fit very well. I could really get into swimming around and eating smaller fish/food but hearing what sounded more like a person get hurt, it threw me off. Maybe consider another chomp/bite noise but a deeper one to signify a "bigger" fish got you?

Layout: I think this game in it's current state could do a solid job on a mobile device where the layout is already set for that but I do think if the plan is also to release for Windows, it'd REALLY benefit from having something with a desktop aspect ratio. This very much felt like a phone game that I could run in browser which is totally fine, but when you're also letting out a Windows download, I definitely think having the associated aspect ratio will make the game feel more polished.

For sure, after this weekend I'm going to spend a lot more time fleshing things out as far as the different builds. The android build is my first hurdle but then Windows & Web are going to be changed a bit too to allow for a wider aspect ratio. Great suggestions, I went with the goofy eaten sound as just something silly but I do like your idea of maybe a down-pitched version or something like that when you get eaten instead. I also plan to add some more animations when you eat or are eaten to give more tactile feedback.