Leaking toilets

Does anyone know/recommend any leak detectors for toilets.
These are for internal toilet leaks only (flapper etc)

thx,
Martin

If you suspect the toilet is leaking through--meaning running all the time, I would replace the flush valve if it is a Mansfield or the flapper if it is other. Hold a mirror under the rim and if leaking you should see a small stream comming out one of the holes. If you suspect or mean it is leaking at the base, replace the wax seal.
On a Mansfield flush, there is a small rubber ring that goes in the most upper slot where the plastic tube comes down after a flush. These are notorious to leak. Not really sure what you mean, but I would replace as indicated above. Another trick that might help is to put a bottle of CLR into the toilet tank and let it sit. It might change the dynamics enough to stop any leaking at the points referenced. It will also clean out the holes under the rim.

Use a color dye. Place it in the tank and then look in the toilet itself and if you see color come through and you have not flushed you know you have a leak. My short answer on the information that was given. The obvious of course is when you hear the running water sound way past the time when the toilet was flushed.