Quite unique idea. There are not many simulator games where you are inside aquatic ecosystem. Fits the theme nicely as the water keeps vaporizing, making the play area smaller. There is the big fish, on top of the food chain and needs to be avoided. I hauled all the fish as a cluster for maximal survival, but things can get difficult with more and more fishes.
There is a problem, if you force the fish above surface, they go off flying. Abusing this bug lets the player use the whole starting space whole game.
Graphics are functional, everything is clear and distinct from each other. The dino skeleton reminds me of some childhood comics. Those old comics use to always have skeletons underground.
Game would benefit from some music.