Here's what I do with a Chemex. I put the Chemex on the scales, add the filter and hit tare (so it's now weighing 0g). I add the 22g coffee and hit tare. Then I add 300g of hot water (same as 300ml). It produces the same cup of coffee every time - exactly how I like it. Obviously, if I ever change the coffee I get (or the coffee I get now - currently an espresso blend which is blended for consistency - changes significantly), then I might need to experiment a bit and see whether 24 grams of coffee is now my preference, for example.