but then it wouldn't sink...
It would most likely be hotter then the water around it, so it would still be on top...
Actually, a better point would have been to say that as it would be to say that fresh water is less dense than salt water and would therefore sit on top.
But I didn't think it was going to be a physics discussion. He said as he rammed an iceberg so far down TFMs throat that he didn't need to drink for a month... (all in a very nice, non-violent way of course)