I use this chart, and as I read it 12PSI gives me ~1.5 volumes of CO2 at 20C, which works out to ~1PSI at 2C. I am happy to be corrected if I am reading the chart wrong, however I pressure ferment at 10PSI at around 20C, and when I cold crash the FZ to 2C my gauge goes down to 2/3PSI. I have...