 The
first thing that has to be taken into consideration is the heat loss. The
main greenhouse structure features closed in walls, and a ceiling
consisting of double layer 6mm PVC with air blown in between those layers.
This still allows some light to pass through, but is still very expensive to
heat. The "tent" structure seen in this photo is actually a layer of
PVC plastic that acts as a greenhouse within a greenhouse. |
 From
the inside you can see the pond. The blue material is a swimming pool cover
which is pulled over every night to further retain heat. |
 Looking
from the other direction you can see the wood stove and a fan to blow the
heat towards the pond. Another fan (not visible in the photo) is
directly above the pond. Fans are cheap to run and effective at
redirecting the rising hot air. |
 Most
of the heating is done with an oil fired hot water tank which is housed in
an adjoining insulated building. |
 Note
the red inline circulating pump. Two orange lines (one hidden from view) are
the circulating pipes. This is the system that keeps the heated water
circulating constantly through the system. |
 The
Tri-Tech filtration units are accessed under the decking shown. |
 The
lid (trapdoor) shown in the open position, is insulated with foam to help
hold in the heat. Note the two orange water circulating lines, these
are the same ones connected to the circulating pump that run under ground
(insulated) that carry the heated water. The steps lead down to the
lower level where the pumps, filters and valves are. |
 The
orange circulating lines go to a manifold mounted directly on the wall.
From the manifold two red lines circulate the heated water under the pond
floor, encased in cement. There is insulation in the floor of the
pond, and all the way around the pond walls. |
 A
closer view of the manifold. On the far right are two outlets to
accommodate additional circulation should I decide to heat my
"over-wintering" in the future. The hot water heater is plenty big
enough to do both 7000 gallon ponds. |
 The
under ground circulating system provides an effective method to heat the
water in the pond, but does nothing to heat up the air temperature.
Condensation and ice build up is result if the pond water is heated and the
air isn't. An oil fired forced air heater is used when needed. |
 Seen
here is a big PVC air duct that runs the length of the pond. When the
furnace comes on, it simply inflates with warm air. As the pipe
inflates, the warm air blows downward out a series of holes all along
the bottom, ensuring even distribution. When the furnace turns off, it
simply deflates. The thermostat is set to 48 degrees F. so that no
harm from the cold comes to the tropical plants. It only comes on during
very cold nights, but I can quickly raise the air temperature whenever I
wish. |
 An
air pump is located by the furnace and water heater in the insulated
adjoining room. This air pump supplies the air to the bottom drains in
the pond. |
 Built
right into the waterfall is a woodstove insert. The woodstove heats
both the air temperature during regular operation, and the stone mass of the
waterfall. Heating the stone up during the day helps overnight. |
 Finally,
a trickle of water over the waterfall is preheated by going through a coiled
pipe above the woodstove then into a soaker hose on the top of the waterfall
before running down the front of the waterfall. This runs continually
and provides an automatic water change. |