the ice must be thick to support it across the pond and yes, the pond must be pretty
deep. this is used in zone 4 and colder, like in Sweden IIRC. Ingrid

On Mon, 26 Nov 2007 10:14:36 CST, Derek Broughton wrote:
Nobody has mentioned a technique usually used for somewhat deeper ponds.
_After_ ice forms, pump a little water out to leave a gap between the ice
and water. This works as well as covering with plastic, but I suspect it's
a bit too tricky to try it with only 15" to work with in the first place.