Good concept! I think this is well on the way to being quite clever, however it just needs more experimentation with colour and maybe adding some underwater type plants or look to the planet (it is Spongebob after all). 3 points.
Gotta give ya props for thinking outside the brick here. Not a bad concept. Build was still a little lacking but I see you put some effort into it. Woulda got a solid three with a bit more to it. 2 points. ~ Chris.