Toilet Tank Gaskets

Q. "How long 'should' the parts inside of my toilet last?"
A.That depends on a number of variables and which parts. Water quality is one of the major factors. If your water source is heavily chlorinated then many parts won't last long. Or if you have a lot of sand or grit or have a low pH or "aggressive" water source then parts simply won't last as long as the 'average' length. Also the quality of the parts matters. The replaceable parts such as flappers and washers/seals generally will last at least 4 to 5 years on "average." If you use a bowl cleaner some flappers won't even last one year. If your flapper has black "goo" on it then it is either due to age or quality of your water and if it feels soft then it's best to change it.