We live in a hard water area, which means taps and shower heads will be prone to limescale build-up, which in turn affects water pressure. Limescale can also block inlet pipes to washing machines and dishwashers, with limescale deposits blocking the filters on the end of the pipe (connecting to the water source).
Taps usually have removal filters on them that can be removed (e.g. with a spanner - carefully so as not to damage the chrome finish) and cleaned. Advice on how to clean the original Grohe taps can be found here, and shower heads here.
You can check the hardness of your water by going to the Thames water website.
Dishwashers and salt
Due to the hardness of the cold water it is advisable to add salt to the salt container in your dishwasher even if you are using dishwasher tablets that contain salt. Please check your dishwasher manual for instructions on where the salt container is in your model.