There are a few things that can help with what you guys are doing.

First thing I would suggest is to never run a tank below 5% unless you enjoy the thought of changing flowmeters.  Ravens are particularly bad about this, but they are also the most accurate flowmeter I have used.  When you start to run out of liquid, it is able to start expanding and that is the jumps that you see in your flowmeter. When they first start to spike I know that I'm real close to empty. Running vapor through the flowmeter is the death blow to Raven flowmeters.

Second is to use your tank alarms. When you hook up to a tank, look at the percentage gauge and input that into the monitor.  In the rate controller setup you need to set the tank capacity units to Gal. and set Tank Capacity Displayed to %. In the alarms tab, you can set the alarm to trigger at whatever percentage you want, I use 10%.  If your flowmeter is calibrated correctly it will tick this gauge off just right with the tank, within 1-2% is what I usually get. When it gets to 10% my alarm goes off and I know I need to be heading to another tank soon if I can't finish pass.  Make sure to set your tank capacity to the size of tanks you are using. Then you just have tap the tank icon on your run screen to fill it back up and change tank capacity, if you're like me you get lots of different sized tanks.

Third you can add an electronic pressure sensor (or two) into the system to display your manifold pressures on monitor to watch for the jumps.  Quick pressure jumps are clear indicators you are having flow problems.

For the most part I always have a main run page with application map on it so that I can look for those spikes. 

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