I was in lfs the other day and heard the story about the tank going through the floor. First thing I did was post the question here ! Damn be honest im still worried about putting the big tank in the living room.
I can sure understand why it would make a guy nervous,,,I just think that with a little research and prep work it's probably safe as can be..(if you can get it up against a wall that helps support the house I am 99% sure you will be fine)
......another thing I just thought of ....put down a piece of strong plywood (bigger footprint than the tank)to disperse weight...throw down a nice area rug over the ply...the wife might even like the look
.... p.s. measure again after filling ....just to make sure it doesn't get WAY WORSE,,,