I did not really think about temperature, so I threw a floating thermometer in the pond and it is around 72. Not warm enough to make them happy, but it will do!

My small pond is currently a ditch formed by run-off from my property. A little widening and I should have a decent 6X12X2.5 deep area that will self fill. Looking at overflows now. Should not be too bad. More details later and pictures of fish. I get it.