Lol, that's a familiar number to me. It's about where my monthly bill sits throughout the cold half of the year; that's for a small, well-insulated bungalow with baseboard electric heat. I don't even want to think what it would be if I didn't use a wood-burning stove...
My supposed rate is just under 9.5 cents per kwh, but of course one must add on the bewildering variety of residential base rates, fees, surcharges, transmission costs, delivery costs, management fees, mismanagement fees, administration charges, equipment upgrade offsets and other mysterious add-ons that keep the monthly bill as incomprehensible as possible. We're just getting into that magical time of year when that joyous holiday chant is heard in the house: "Yeah, I know it's chilly; put on a dang sweater and shut up!"
I have gotten completely fed up with fighting nature and paying for the privilege. Heating water to keep "tropical" fish when you live in an arctic wasteland no longer holds any appeal to me. I now have only one system of a couple hundred gallons that is actually heated to 74F; all the rest of my tanks are unheated, and almost all of them are in a basement where the ambient winter temp will be around 60F, give or take.
It's not just the money, either. No matter how you set up the heating, the fact remains that things can go wrong and they usually do so at the worst possible times. Keeping coldwater or temperate-zone fish removes a large source of hobby-induced stress and worry.
Heater controllers sound like a great idea, but...the thermostat for the controller is in one tank. It turns the heater on and off to maintain that tank at your set temperature. Sounds great, but if you want other tanks with similar control, you really need a separate controller for each tank system. Otherwise, the second tank's heater turns on and off based upon the temperature of the water in the first tank. The heater wattage would need to be perfectly matched to the volume of the tank for this to work; that's never the case. The ratio of wattage-to-volume will vary from tank to tank, and therefore a single controller will keep its own tank at the perfect temperature but the others will all be kept higher or lower. This doesn't even take into account the varying rates of heat loss from various tanks based upon shape, covered/uncovered, construction material, air movement in the room, etc.
An important factor that doesn't seem to get enough attention is the heat generated by other tank devices, specifically pumps. Simply selecting a submersible pump rather than an external one can make a difference of several degrees in tank temperature. I use only submersibles for that reason. Any pump is going to waste a certain amount of energy in the form of generated heat. Why not take advantage of that heat to help keep the water warm?
