Inspired by discussion here, having run out of "official" descaler liquid, I bought some citric acid (from Wilkos, for laundry).
When I was using the liquid, I put 125ml and then topped up to 1400ml.
How many spoons of citric should I use for the best result ?
(Just an added wrinkle is that I notice the official descaler is *lactic* acid, not citric - not sure if that makes a difference).