toilet flapper closes too fast
a 5 y.o. AS 4396 w/Fluidmaster guts.
The flapper is closing too fast, and I think, always has.
There is a captured donut of polyfoam (of some kind) right on top of the flapper.
The chain is as tight as I can make it, less then a 1/4" before action.
The take fills to less than 1/2" below the overflow.
Could the donut be water logged, or should I try to add another?