@ Panhead i also would like some info on geothermal cooling, i have x4 res tank and chillers isnt a option
@ drgreentm I dont use any other GH products just the nectar
This is gonna be a long response but its needed to understand how much work went into making this idea work.
I used to be in union commercial and industrial construction for 30 yrs,i got the idea one day while i was in a boring ass meeting,i was watching the HVAC guys installing underground lines for the geothermal heat/cooling system & asked their foreman if it would work for my application,he gave me the info to where as long as i was well below the frost line i'd be good to go but in the coldest months i might need to heat the res a bit.
We dug pits 4 feet deep & put a 50 ft coil of tubing in the pit & covered with sand then soil,connected one end to the pump & the other end to the table but we had a ton of problems,it took about 75 gallons to fill a 55 gal res plus we had flow issues so we gave up & went back to running the chillers.
I was watching This old house & they burried a big ass water tank for watering a garden & it hit me,why not just bury the res & use normal lengths of tubing.
We tried it with a single res 1st,we dug down 4 ft again & put plastic 55 gal drums in the ground,to protect against tree roots we mixed rock salt into the soil & backfilled to within one foot of ground level,then we repoured concrete to finish the flooring,it was an instant success for keeping the water cool but it was too cold, we added a fish tank heater & it was perfect but not without another problem.
We burried the top of the barrel even with the new floor top which was a huge mistake,contaminents from the floor would get into the res,we liked the results so much that we decided to go geothermal with all the tables with a few changes starting with leaving each barrel about a foot above floor level, with the lids installed there is no chance for contaminents entering the res.
On subsequent barrels we added a no float sump pump that we hard plumed with the discharge outlets feeding directly into the grey water lines of the bldg,this way when we change the res's all we have to do is turn on the sump pumps & in about 6 minutes all the res's are ready to refill or clean,we also added dedicated fresh water lines directly to each res & connected a short water hose that goes through a hole in the barrels lid along with the lines to & from the table.
All this was great but trying to ph the water was hard,we ended up putting a bluelab tri meter system in each res at a huge cost but it does make the grow much more efficient.
Each table has its own res ,which in turn has its own table pump,sump/discharge pump,discharge lines,fresh water line & tank heater,the trays are all set up on wooden tables made from 2x4's & plywood & the legs are all set on heavy duty casters ,the system sits directly over top its res to block light, we roll the entire system in & out for maintence & harvesting,when finished we restock the table & roll it back into its
place.
Keep in mind that we own our bldg,its one of the rental properties my family owns that is in pretty bad shape visually & we couldnt find a tennant for years so when we bought into the co-op we used the whole area for our grows.