I've tried to convince my wife more than once that a small hole wouldn't be visible. Oh well.Good point Pete. My 30lb'er is in the basement below and ~15 feet away from my 30G tank. Upcoming 75G will be about 20' away in the basement.
Not everyone has basements...or the desire to put a hole in the floor (though a 1/4 or 3/8" hole next to the wall is darn near invisible, especially behind the tank)
--Don