I know a person that has two toilets in their appt.The one toilet will lose the water in the bowl but it doesnt seem to be leaking,and it doesnt always do it. The parts in the tank work just fine and the bowl fills like it should. Is there a problem with a vent in their appt building(duplex)? No leak on the floor or in the basement and the unit is rock solid on floor. Thanks you guys for your help again! Ahhhhh one last thing Go Bears!!!