No problem! I'm sure most people don't sit around thinking about whether or not fish drink water :). I do find it to be an interesting question. I would be a fan of teachers using this information to explain osmosis to students. I think the question of whether or not fish drink water is distinct enough for it to stick out in someones mind long after a lecture. Although sometimes I have a hard time separating what most people would find interesting from the stuff that might only be fascinating to me because of my interest in fish.