Learn how to identify where the toilet is leaking from and how to fix the leak with this straightforward guide. Find out how to replace a fill valve, tank bolt or spud washer to stop your toilet from leaking. For a toilet tank that is leaking, you will need a toilet tank repair kit
Toilet Leaking From Tank Into Bowl at Valeria Sturm blog
This will repair a leak from the bolts that hold the tank to the bowl and the gask.
The most common internal toilet leaks are found around the fill valves, tank bolts or spud washers