Kettle level guage

A kettle's fill-level is often shown by a transparent layer directly showing the water, often supplemented by a float to make it easier to see. The problem with this approach is that the fill level indicator is affected by limescale deposition, reducing aesthetical value. A possible solution to this would be to have the fill-level indicator in a separate compartment (with no water in). The indicating object would be magnet, and held in place by a magnetic float on the water side. This would work similarly to a magnetic window cleaner.