I also use one of the overflow devices shown by Dr. Tim, but I only have 1 barrel then a overflow pot, either a 4 or 5 gal SS pot. As soon as I see a solid flow thru the over flow tubing, I shut down the filter. At the times when I have enough for another barrel, I first tighten the bungs in BBL 1, move it and then set up to fill #2. In those cases, I then pour the over flow contents back into my mix tank and restart the pump.
Before I had the over flow device I had to keep a close eye on the barrel as it filled and I made a mess more than once. It has saved me untold gallons worth of syrup in the 5-6 years since I bought it.
Dave Klish, I recently ordered a 2x6 wood fired evaporator from A&A Sheet Metal which I will be converting to oil fired
Now have solar, 2x6 finish pan, 5 bank 7x7 filter press, large water jacketed bottler, and tankless water heater.
Recently bought another Gingerich RO, this one was a 125, but a second membrane was added thus is a 250, like I had.
After running a 2x3, a 2x6, 3x8 tapping from 79 taps up to 1320 all woodfired, now I'm going to a 2x6 oil fired and a 200-425 taps.