i personally didn't like the animation of this video. it was scary..
the robot was a symbol of human. it used up water very quickly. which i thought it indicated that we humans use our important resources excessively just like the robot used his water very quickly.
the meaning of the tree and fish in a weird location and the robot taking it was that we try to take land, resources from places that are not supposed to. the moon or "territorial" airspace is a good example. it isn't for us humans to take, but still, we try to have it all to ourselves.
i did't get the part where the robot put the fish in his water tank though... maybe it means that we should reconsider about using all those resources? i don't know.. :/