Originally Posted by novahokie09
You go to great lengths to measure temperature, which you yourself admit has little influence on efficiency. However, you don't measure your volumes, which has a much larger impact on efficiency. It just doesn't make any sense.
not making any sense. The OP stated multiple times including in the initial post that he/she is measuring and tracking volumes including final volume in the fermenter and nothing has changed.
Quite the puzzle, that is a pretty huge efficiency drop for someone with so much experience on their system. I'll have to go with the last few suggestions to check the water report/pH. I would think it would have to be a pretty significant change to result in such a drop, though. Not sure if you've read any of Kai's articles on his braukaiser site or if that would help at all. This one
on troubleshooting efficiency talks about narrowing it down to conversion efficiency or lautering efficiency, maybe something to consider next.