Date to fill above ground deck pond?

[kumdoalan]

If any of you have an above-ground deck pond, (Wooden box with a liner inside) what date do you set it up, fill it, and add the fish?

I live in northern North Dakota, and right now it gets to near 30 above zero in the days, about 12 above at nights.

I wonder what temps would be needed before I dare fill the pond and add fish?

 

[Dr Joe]

65*F at night minimum with no chance of frost w/o a heater.