We finally bought material to build the aquaponic and heating system, its all fun from here on out hopefully.
After digging the trenches to the desired width we raked them flat and added gravel in to the sandy soil. We then packed down the floor with a gas powered tamper to get a solid surface to rest the pylons on.
After tamping we leveled the bottom with a 2x4 and a level and we laid down 1/2" wire mesh to prevent any woodland critters from digging in to the pond liner. On top of the wire mesh we added a layer of sand 1-3" thick to bring the floor to the proper height and leveled once again.
Areas where the beams touched the ground were cleared of sand down to the tamped soil/road base.
Pylons set in place and brought to the correct positions with 2x4 framing. First the 4x4s were set at the correct intervals, then the width was set with perpendicular 2x4s. After setting the width all that is left is bringing the poles to a vertical and making sure they are square.