Most incredible aquaponics set-up I've ever seen

[Grant H.]

And then is the base temp in the winter 68 as well?

It drops off a little during the winter, down to low 60's, but it makes heating a lot more reasonable.

Very interested in your design, implementation and approx cost If you feel comfortable doing so.

I'll have to get pictures from my brother, but in text form...

He has a crawl space instead of a basement, so we punched the lines through concrete block foundation wall, and then pulled bundles of 4x pipes through into trenches that we dug into the yards. We dug 4 trenches off the house, one on each of the 4 corners (nominally NE, NW, SE, SW). The trenches were dug to line up with the bottom of the crawl space so they were only 4' deep instead of going down to 5-6' like would be recommended, hence the temp swings.

We started the idea with pulling outside air through 4x 40' pipes in each trench, which worked decently, I don't have all the log data here, but it wasn't as good as we were expecting, and you have the issue of open vents in the yards, critters wanting to use the pipes for their own purposes, etc, so we decided to change it up for a closed loop system. We looped the 4x pipes in each trench back into the crawlspace and then ducted the loops and added a large squirrel cage blower.

By doubling the length of the pipes, and pulling air from the house to cool/heat, we improved the capability of the system dramatically. It also eliminates the humidity issues that arose with the open ended system. We've had to play with blower speed and size to make the use of the loops the most effectively, and it's taken a bit, but with data logging and lots of temp sensors we have come up with what seems to be the most efficient use of the loops.

You have to be aware of the size pipe that you use. The less pipe cross section you have, the higher the pressure you have to run through the loops. That is how we ended up with 4x loops of 4x 4" pipes for the house. Other folks that I have seen talk about similar systems are using 12" pipe, but they are generally using corrugated plastic or PVC, which of course doesn't have the thermal transfer properties of the aluminum that we used, but it can simplify the blower and other equipment required for the system.

I'll see what we have left of the planning stage, which wasn't real thorough (we're sort of fly by the seat of your pants DIY'ers...), and see what my brother has for data logging and other information.