Hi guys a quick question for the Biab Brewers. I'm doing my first Biab on Saturday and have 6.2kg of grain. I'm using a 40litre buffalo. Brewers friend says I need 36.2litres of water. My equipment settings were for 2 litres of dead space but having just done a test it is actually 4 litres to the base of the tap. If I increase the water to 38.2 litres I fear it will not all fit in even though the 40 litres mark on the boiler is a good 2 inches or so below the rim. Questions, can I just siphon into the FV therefore makin dead space losses zero? Is the only way to do this to sparge 2 litres over the grain after pulling the bag? Thanking you in advance.