We check every batch that comes off our evaporator using our hydrotherm. We used to use a refractometer but I didn't trust I was getting accurate and repeatable results in our cold sugar camp.

Now that we have a 2-sided syrup tank we draw off about 20 gallons, slide the empty side of the tank under the auto runoff, stir up the tank of unfiltered syrup, check density using the hydrotherm, adjust the density using permeate to 66.8 Brix, add filter aide and start the filter. We are able to be very accurate with our density with this method.

While it would be ideal to not have to adjust the density we find it is a lot easier to thin the syrup by 0.5 Brix than it is to thicken 20 gallons of thin syrup! We intentionally aim to draw off at about 67 Brix and if it's a hair thinner we are still ok, if a bit too thick we are adjusting down by 0.5 to 1.0 Brix.