It started with wanting to grow food year round...yet at 3k' we have weather that prohibits most veggies from thriving...fall thru late spring. I designed and built my greenhouse into a south facing hill with walkways between grow beds dug into the soil to use the thermal mass to help maintain a medium temperature through the year. This greenhouse was originally going to house an hydroponics system but, with a deeper comprehension of the total dependency on outside sources and the draining of the toxin laced H2O, I looked at the hydroponics system as not for me.
The sunlight enters from a 24'x44'x53 degree 9" TGIs supporting Solex glazing face. The defused light is cast over 1100 sq. ft. of floor and 40 inter-linked 55gal. barrels (radiant heat and cooling) against back insulated wall...behind which is the elevated (for gravity flow) fish tanks in their non- insulated north side room.
The fish tanks are 4'x4'x8'x1/2" HDPE, welded here at home and slid into a subterranean level to maintain constant temperature approx. 56 degrees F. From the tanks H2O gravity flows into the grow beds which are ebb and flow design...from here the H2O continues on a gravity flow to the sump tanks pit. The tanks are 4 @ 550gal. ea. sitting tightly together in a concrete walled roof covered pit to keep them cool and protected (no sun reduced algae growth). Here at the sump tanks are the only H2O pumps, their flow rate exceeds the requirement necessary for the fish tanks/grow beds, so here one valve diverts extra H2O overflow back into the sump tank and the other valve to the fish tanks/grow beds.
I am introducing a secondary system from the diverted H2O overflow which is still very nutrient rich less the solids and now has another opportunity to service more plants. The overflow will be pumped back to the greenhouse and up to a second level of raft grow beds...a great area for lettuce, cilantro, and lots of arugula.