The icy waterfalls are pretty and out here they can last all winter. I sort of hate to run my pump (3000 gph) all winter because of the cost involved, not to mention the possibility of freezing solid the skimmer box inlet to where the pump is. If that happened, the pump would burn up. And believe it or not, but I was told by my koi distributor that the pond will stay warmer if you donít run the pump. HmmÖ Should research that more, eh?
Ponds that freeze over can winterkill fish because of lack of oxygen. Breaking ice with a hammer or rock can hurt the fish, like a concussion grenade, so in time you may want to invest in a stock tank heater. It wonít heat up a large pond but will keep a small area thawed out which is the most important thing.