Bobby, I followed your build for a while and really you have it covered. Chiller is a must for this setup I feel. Ran nutes every 15 mins for 30 seconds. Damn thing really sounded like a waterfall when it was on. I think you may run into a problem where the 4" necks down into the smaller line on the return. Rootclogging...but its also something easily fixed later on down the line if it does happen. At that point you would just wet-vac out the unit and put in a larger line.
On my set-up I ran a return line from the unit through my wall (basement) and down into an underground thermal cooling loop.
Dug a hole 6 feet down and 3 feet in diameter. then I coiled up 150 feet of 1" sprinkler hdpe tubing into it, the return came back inside to my reservoir. All summer the water was around 63 degrees. I did just bypass it for the winter though....way too cold!
Also my column were black so they warmed quite a bit till the canopy covered it. With your white tubes it will be better. May even be worth wrapping it in foil. I put clones in and immediately ran 12/12. Nutes were homemade copy of aqua flakes at 1.4EC along with homemade
calmag+.
Just remembered you run cooltubes, so you may not end up with that problem at all.
Plants finished around a foot tall but were all bud. Local strain named Jack. Heavy Indica so not Jack Herer. Ran for 8 weeks then week of flush. Tried Molasses at one point and frothed so bad it was disgusting, dumped within 24hrs. Never again in hydro.
all I can think of for now but ask anything you think of -BB
