my electric bill with all my tanks here in montana is way cheaper than just having 3 tanks in north carolina. My power bill runs about $75 a month. My water bill runs about $15 per month. As for the pond, when it is very cold you will need an insulated lid. I built the pond jacuzzi style. It has hella insulation all around it. 2" plastic coated foam insulation all around, all gaps filled with great stuff, and inside of that insulation regular attic insulation in 16" batts. The lid has blown in insulation on top about 7" thick, and underneath it has the 2" plastic coated foam insulationl, all wrapped in a tarp. As a suggestion I would use something besides a tarp as it does not prove very water resistant and all the insulation there is now soaked. Just for gee wizz the pond is now in my garage, the outside deal was a temporary fix, because my idiot landlord wouldn't let me keep it in my garage at the time. I now am buying my own house, and I am going buck wild on my aquatic hobby. 2 new tanks in the plans right now. Hoping to at least get my 300-350 gal aquarium up and running this summer, and next summer have my 2500 gal aquarium up and running. Oh, and with all that insulation once the water got to around 78 f. it stayed there and the heater barely ran at all unless I opened the top to feed. Hope this helps. Where you are I would get one of these cattle troughs and bury it, there shouldn't be perma frost where you are during the winter so you should be fine to bury it, and just make an insulated lid for the winter. That will save you lots of dough.