jamiel - lol yeah, that happens.. I’ve learnt to never run out of citric acid powder.. once a month I run the coffee machines and kettle with it.. they look like new, but it needs constant attention so if I see some scale I have to deal with it right away. Ironing requires deionised water, I had to bin my last iron, it started coughing scale buildup
Dixan - might try the W5, calgon is overly expensive for what it is
Laundress - aren’t the ingredients I’m calgon byproducts from different types of Washing soda/soda crystals and baking soda?