I have to admit I haven't read "the bible" but from experence, 20s nights + 40s days = big sap in the tanks. I'm wondering if my taps holes are drying out? I've got all mine on tubing, and tapped in on the 2/21. I just seems strange that they ran great sat/sun and squat on mon/tues. We haven't had any precip. in a while...could that have something to do with it? I can't comment on sugar content....don't have a sap hydrometer, but seems to take about the usual time and volume to turn sap into syrup