I find after about 2 years I have to divide my peace lilies. I can't just keep snipping of dead leaves and topping the plant up with fresh soil. As a result every 2 years the larger plants get repotted. Incidentally even if they are in bloom they get repotted - this is because I end up with a narrow weather window when I can do this - and they haven't died yet.
In regards to adding new soil you need to make sure the roots are covered and that means covering up to the "mark".
I find after about 2 years I have to divide my peace lilies. I can't just keep snipping of dead leaves and topping the plant up with fresh soil. As a result every 2 years the larger plants get repotted. Incidentally even if they are in bloom they get repotted - this is because I end up with a narrow weather window when I can do this - and they haven't died yet.
In regards to adding new soil you need to make sure the roots are covered and that means covering up to the "mark".