Over wintering

[Akai-San]

What is required for over wintering outdoor ponds where temperatures reach snow fall levels? How do you protect or insulate outdoor filters? Something I never really had to think about in Hawaii...But Japan is a different story.

[marco]

I cover my pond with polycarbonate and protect my filter with polystirene , but I don't close it too much just to allow gaz ecxanges. I have a heater and try to keep the water around 18 C° in october and november and will let go slowly down to 7 C° for 7 weeks, them I will increase it slowly until spring.

Hope it's the good way , just tell if you have a better idea.
Marco

[butterfly]

I have a 6000 gallon pond 4 ft deep. I disconnect the filter completely around Thanksgiving and let the pump run continuously. It certainly reduces freezing even in O F outside temperature. I do not use any kind of pond heater. I also loosely cover the pond with two layers of 3 mil polyethylene sheets with about six 2X4 wood plank support to prevent snow and leaves from falling in the pond. I change water and start the filter in April. I have been doing this for five years in southern NJ and never lost a fish. Hope it helps.