Same here, have run it with just ice at the strip. 50/50 antifreeze/water otherwise. Trying a few things to get away from the ice, but nothing we've been able to test well enough yet. And in the famous (or should be) words of Vortecd:
"without DATA, you're just another person with an OPINION"
" without a real world test, it is all a guess"
So trying to test....