What pump parts to replace?

laf10

I just bought some new membranes for my medela Pisa and I'm just wondering what other parts are supposed to be regularly replaced? 

jkfranklin

The LC at the hospital mentioned the tubing if you don't let the pump run for a few minutes after each use because they can get mildew in them. That is all I replaced on mine except a bottle that somehow git stored away not clean. Whoops!