Originally Posted by Reverend JC
Make sure the thermometer is calibrated. I used one i thought was right for three batchs until i realized it was off five degrees and that caused my eff. to take a dump on me into the upper 50s. back to the original thermometer and im back to 78% eff.
That was one of the first things that I thought of as well, but I used the same thermometer on all 3 batches, and it's calibrated correctly as far as I can tell.