I fixed mine - took about an hour because I was learning... Between the two is a doughnut shaped washer compressed by a metal plate with the pressure applied by two wing nuts - at the back - one each side - pointing downwards. You can often fix a leak here just by tightening the wing nuts... Otherwise buy a new doughnut washer kit from a DIY store - Turn off the water supply - flush the loo - undo the water inlet pipe - remove the two wing nuts - remove the two fixing screws at the top of the cistern that hold it to the wall - carefully lift the cistern and tip any remaining water into the loo. In my opinion the "seal" does not require any sealing compound - the squishyness of the washer and the relatively low pressure are usually enough. Check also by squinting at the washer from the side - it should be thin and above all parallel - if not parallel you will never get an effective seal. Good luck...
Peccavi
August 2010
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