I totally understand mL but when talking about how much nutes you are adding to how much water it's used like 0.5mls/L or 0.5mls/gal so someone reading it knows the quantity of nutes in relation to the volume of water. The way you were posting it I couldn't tell whether you were referring to mLs per liter, gallon or the total volume of your reservoir.
When I do DWC I just add nutes as I go along until after the stretch then generally do a flush and refill with a flowering mix for the final 5 or 6 weeks of an 8 week strain.
I very surprised that you have problems with the lights lower. These are HPS bulbs and not some LED lights right? I looked up the name on the hood the lights are in and it says HPS. I have two of those and I think one ballast just died on me. I was using it to light up the lower portions of my plants as I have seeds ripening down there. I swapped in my 85W - 5000K CFL to finish that job.
Are the 150w bulbs just standard HPS or some special type for growing with? I know they make ones that give MH type light from an HPS ballast for vegging but they are damned hard to find when you don't shop online.
These are all Ceramic Metal Halide bulbs made for HPS ballasts.
Eyelighting.com sells a 150w Cera Arc. Model: CM150/U/837/MOG/EN
SunPulse has one, SPCMH15032K
And GE makes a couple that use standard size sockets so you need an adaptor, E39 - E26, to use it in the larger mogul socket. I got one at Home Hardware for about $6. Using it now with that 85w CFL.
Models: 150U830Med/0 and 150U942MED/0
The thing with net pots is that they just act like a support for the plants. The root system is in the pail or tub so the size of the pot makes no difference to the roots. Just that the larger the pot the deeper it sits and takes up space for more nutes in a single pail or tub. With a recirculating system it doesn't really matter about that.
These 5" net pots worked pretty good with 5 plants in each.
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