You are more likely to see scale in water boiled in plastic kettles than metallic ones because they are smoother and hold the scale less firmly. To reduce scale:
- empty the kettle and rinse out frequently, every day if necessary
- try gently brushing the insides of the kettle with a stiff nylon brush to dislodge the scale
- fill the kettle with a solution of vinegar and water and leave it for four hours. The kettle should be rinsed, boiled and rinsed again before reuse
- use a descaling solution available from most hardware shops and chemists - please follow the manufacturer's instructions.
Some water filter jugs can partially soften water to reduce the formation of floating scum. If you choose to use a filter jug, please check that the replaceable cartridge is designed for softening and always follow the manufacturer's instructions.