Planning trip to Florida in the fall. I live in Indiana. What if on return trip...in mid October I get caught in freezing weather for one day or evening. Assuming its as low as 27-28 degrees can I put some RV antifreeze in the tanks as assume I will be ok? What would be the best solution for the one day or two problem of a mild freeze. At what temperature should you get concerned? I would not think there would be damage if only in high 20's in evening and warms up during day?