On this cool first day of October, I am sitting inside planning the interior of my passive solar green house and trying to justify (and heat) an aquaponics set up for raising talapia in Southern Oregon (Northern Jefferson). I need to state first that I hate the cheap throw away culture represented by plastic IBC totes. I was very fortunate to spend a summer working in Europe during my college years and really appreciate the way the farms were built to last many generations; stone fences, timberframe barns etc. It seems to me that a plastered tank would increase the thermal mass in the greenhouse and provide some thermal inertia necessary for stable water temperatures.
The question then becomes how to heat the water? I am planning to sink the green house 4 feet into the earth to take advantage of the mean average temperature here of 56 degrees. Talapia thrive 70 to 85 dgrees. I've seen Paul's video on rocket mass heaters in green houses since 2010. (still waiting to see how the build turned out and get performance data..)
My problem isn't extreme cold or deep snow, it is days with no sunshine.
More to the point.. it seems to me that hot compost is a more permie solution. You get long steady heat with little input once it is started, you get great weed seed free compost.
Aquaponics require pumps to circulate water and pump air to raise the O2 in the fish tank. I can see a solar panel working in the summer, and even running a swamp cooler, but what about the winter? We do not have reliable wind here, possibly micro hydro.
Any thoughts? Anyone done something similar?