Russ Wilson is using the same concept in a "portable" system. He "insulates" everything that's exposed to the cold except the top surface of his tank, and then uses continuous flow to keep that open. Keeping the amount of surface you have exposed of course "helps", and that's why he's able to make that work. Keep in mind that he's located in Pennsylvania... and just mentions that it has worked up into Canada to -14F. In other words, he isn't USING this system, with lots of animals depending on it, in those kind of temps, on a daily basis. One or two days at that is one thing, weeks, or even months sometimes, without a reprieve, is another. I can tell you that I am watering about 90 head with a hydrant just "running" at a reduced rate.... but that WILL freeze/has frozen up on me, and I intend to change that out to what I've shown here previously, where EVERYTHING is protected from freezing, all the time (unless of course the electricity/well shuts off, and the cattle drink the tank empty).
I don't want to have to worry about it. Worst case scenario, the above DOES happen... I cover the tank and put a propane heater inside it to thaw the pipes on the floor out, and turn the water back on. If something did burst, it's ALL above the floor to work on. Incidentally, if the well does quit, the pressure will eventually drop on the supply line... and as that happens and the water in the supply line begins to draw "back", it will allow the air valve to open, thereby allowing the water in the hydrant to drop down below the frostline... which is where???.... above the floor of the tank in this case (because the tire is big enough that it has been protecting the area under it... so there's no frost underneath the tank where the pipes are anyway).