Leaky closet spud gasket: the rubber gasket sealing the toilet tank to the bowl may be leaky, or fittings securing the tank to the bowl could be leaking. Watch out: If leaks are at the toilet tank mounting bolts you will might see water on the floor. But then again you might not. [...
A flapper is the rubber part of the system within the toilet tank that lifts up to release water into the toilet bowl once you flush. After that, it goes back down to seal the opening and let the tank fill with water again. The most common reason for a leaking toilet problem is when...