I've seen @MyQul recommend adding 9% flaked barley to aid head retention..... Say I've got a 1kg grain recipe - I'd expect to mash with about 3L water, sparge with 4L, and at the end of the boil end up with 5L. If I add 9% flaked barley do I need to reduce the other grain(s) to keep to 1kg (or alternatively increase the water to keep the grain:water ratio the same)? Or is it such a small difference that you don't really need to worry? Reason for asking, I'm currently drinking a very nice black IPA which prompted me to Google, and I found this simple recipe which I'd plan to scale back from 5USGal to 10L but I'm not sure how to factor in the flaked barley: https://learn.kegerator.com/recipe-dark-forest-black-ipa/ I guess maybe the simple solution is go easy on the water, and then liquor back in the FV if the gravity is still a bit high???