My first thought would be go buy a gallon of liquid chlorine (or liquid shock) from wal-mart, k-mart or wherever. Check the label to see it lists Sodium Hypochlorite and the concentration (should be 10.5 or 12%). Then buy a gallon of ultra bleach and you should find the same ingredient listed but at a lower concentration (5.25 or 6%). Now you show her that laundry bleach is the same stuff only weaker so it is even less dangerous than what pool stores sell.

Peter