There was really only one big complaint I had, and that was the movement. It was not easy to move around with the arrow keys in the way you had it set up. It's more traditional that w moves you in the direction the mouse faces, but that was not the case. I think a mouse sensitivity would also have been a nice feature to add, however, a time constraint will be restricting, and not everything can be added with that restriction.
Good job with the camera movement, fish AI, and background atmosphere.