Many questions

[Bob]

no body has tried that that I know of  for the reasons Manta has described.
(good answer Manta!)
...
Randy is trying out a LED on his reservoir tank to add a small amount of heat to it when parked....
 progress... it seamed to be working but that's the last I hurd of it! <GRIN>
....
Bob...

[randy]

it seems to keep the cell from freezing, But, I noticed an air bubble in the return line a week or so ago, that makes me think the bubbler had ice on the top pushing the gas out the bottom, next hard freeze I'll check it.

[sixpack127]

I have read in other posts that the higher your concentration of the electrolyte - the less likely it is to freeze - the only problem I currently see is the bubbler - how to keep clean water from freezing - if nothing else - maybe a small heater with a timer on it to start the system after the water has a specific temperature - I could see this more for us in the northern tier of states