Viability: The game seems to run and works well enough. I was able to move and grab the pellets and didn't clip through walls. One problem comes in with knowing the objective. Sure I get points for collecting the pellets, but what else am I trying to do? I'm a little confused there.
Presentation: The animation is very cute and the pellets floating look works well in trying to give the game an underwater feel . I think things are a little to zoomed out or zoomed in. I don't know where I'm trying to go most of the time.
Theme: It's quite relaxing and fun. Def has a calming effect on the player. No worries, just swimming.
Engagement: Calming, but I'm often wondering what my objective is. If I had a screen to help me know why I'm there, I would be even better immersed.