Can somebody please explain to me how to use the efficiency tool in the Brew Day section of Brewmate? You have to input Actual volume in kettle, Actual OG, and this calculates Actual brewhouse efficiency. What has me puzzled is the definition of Actual volume in kettle. Going by todays brew, if it means actual volume in the urn (including trub) - I;m a BIABer - then my eff was 97%. If it means the hot volume in the cube then eff was 81%. If it means cooled volume in cub then eff was 78%. Any ideas? Randy Rob?