My PPL bloom box has 3 600w lights in a straight row of air cooled daystars (6"max fan on intake and out end of a/c circuit). I reverse these fans to heat the home in winter, blast straight outside in hot months. I run digital ballasts with sunpulse bulbs and have one magnetic to run hortilux hps. Supposedly the 20,000+ Hz that a pulse start digital/e-ballast hits the arctube with squeezes the (heavy metal, and very not organic, ie toxic) gas cocktails slowly out of the vents in the sockets of the bulbs. Where they end up is in our/our ladies' environment and in the plants themselves, yay modern industrial systems (yay a true independent a/c light circuit too).
Currently I run a 4K Sunlpulse on the "entrance" end of the box, the magentic horti hps in the middle, and a 3K Sunpulse at the "exit" end of the box which is occasionally swapped for the 10K finishing Sunpulse. Ya Ya its a lot of halide, but I am in no rush and am growing mainly for resin quality and I love to make organic RO IWE. The box is 7'x4' with a lovely 9' ceiling
. I take out one 600w and use only 2 lamps on a gualala light rail in hot months, also have a little r2d2 style AC unit that I can install in hot time too. I tend to prefer about 50 watts per square foot of 600s. With 3 its over 60wpsf. Too much light is possible for sure, any desert outdoor grower has seen their fair share of that! Genetics must be able to tolerate said intensity, its easy to raise em up a bit tho too. On the other end I have seen decent smoke come out of 25-30wpsf intensity gardens with crusty old bulbs, again genetics play a role on this end.
Veg is in another room with 2 tents a 2'x4' with a 3' light rail with a 400w 6.4K sun pulse. Then a 4.5'x4.5' with a 600w sun pulse 6.4K also on a 3' rail. If its hot the veg may down size to a 250w and a 400w as its only on my swamp cooler in there. 12/12 bloom 20/4 veg.
At work we have flipboxes and banks of 1000 watt digitals running hortilux 1000w hps in 3 bloom rooms. In veg there are 4 thousand watt hortilux standard halides and T5 units for younger plants, getting a 6oow stage set up soon too. We do TLO here: 4x4, 1 gallon, 5 gallon plastic nursery pots then a 20 gallon smartpot with TLO manure, layers, 2.1, super living EWC top layer, usually 6 spikes varying types by variety, and cocoNot used as mulch. So far so good, the plants are WAY healthier compared to those grown with my help in full synth hydro at the first producer I worked for, before getting a producing gig that was much closer to my own personal organic gardening ideals.
Tea is more than a human beverage at the new gig!