Brian Bales wrote:Interesting ideas. Its a tricky problem to solve and there doesn't seem to be a lot of information available. I live in a relatively warm climate so my heating needs are minor, I'm in I think a zone 9 so it gets cold enough to freeze but its not a lasting freeze. In the long run what I'd really like to achieve is an aquaponic greenhouse that is mechanical instead of electrical in design. I was thinking maybe wind pumps for moving the water and rocket mass heater for heating but I am far from there. To start with I am going with solar and trying to keep the design to a single pump and an indexing valve. The RMH bench has some interesting possibilities but where I keep getting stuck is on how to implament it. I first considered running the ducts under the grow beds and heating them thus heating the water for the tank and the greenhouse as well but I wonder if it would be sufficient to heat the water. I also worry about the ducts getting to hot and possibly catching the frames of the beds on fire or melting the liner, there is also the chance that the heat might damage the plants in the beds if it gets too hot or the extra heat might dry the beds out too quickly.