Tank to bowl gasket is not formed correctly. You can not tighten the bolts all the way to make the tank sit firmly on all four ceramic contact points. This will distort the tank to bowl gasket causing it to leak. As for the tower, it is also poorly designed. It needs a float to hold it open for a second so we don’t have to. Otherwise it won’t flush a single square of toilet paper. I made a temporary float for the tower out of spray paint can lids and wire ties. It also needs the whole chain position / tower catch thing rethought. My handle lever seems to be in the way and it’s too short of a distance to do any real adjustments. I can honestly say that I’ve never had a problem with the tower gasket. If this starts to give me problems, I’m sure I will replace the toilet immediately.