It’s not leaking on the floor. The flapper just doesn’t seem to be tight enough to keep the water in the tank. We replaced the flapper thinking it would solve the slight leaking, then refilling a little, problem which recurs over and over about every 10 minutes. It is still needing to fill itself every 10 minutes or so to keep a full tank. Did we get the wrong flapper. It was a universal type – our toilet is Gerber 1.6gpf. The flapper seems to fit just fine but why is it stil leaking water out of it?