>A better method is to buy a 12 volt heat blanket such as that
>sold by Camping World catalog (Bowling Green Kentucky; everyone with campers
>on the list should get this catalog by the way). The blanket
>goes around the drinking water tank and when it senses the tank is 35 degrees

Derek.
Could you please post complete address (and an 800 number, if possible) of the
Camping World outfit so we can order the catalog.

Asghar Bhatti 
mabhatti@uiowa.edu