Following as my TT looks foul after one use x.x
Viakal limescale remover spray, no need boiling. Let it stand for a few minutes and rinse it well.
Baking soda/powder works wonders just put a teaspoon on the hot plate with some warm water and leave for about an hour and then rinse the whole thing well
We used white vinegar.
@Alex I had lemon juice concentrate in the cupboard 45ml of that and 45ml hot water worked a treat!!
A bottle of white vinegar is about 30p in Tesco I use it to do my kettle, clean mirrors the toilet an the steriliser you only need a small amount
I use cleaning vinegar but I think you can get the actual tablets that are used for coffee machines x