I'm going to try a Thomas Hardy's clone on Sunday. It will use 26 lbs of Marris Otter for a 5 1/2 gal batch. This will be the 1st time I've tried making another beer right after using the 2nd runnings. I'm going to add the specialty grains and 3 more lbs of Marris Otter for Orfy's 80 shilling scottish ale recipe, after the 1st sparge for the Hardy's. I'm taking a SWAG at it and figure I'll need about 6 gal more sparge water in order to extract the sugars that are left in the malt. Has anyone else here made a second beer from the mash of a big beer? If you did how much sparge water did you use?