While I dont grow autos, I have started seeds under 1000wHID since the beginning of HID use for weed. Around 1977-78.
I run them at 24 inches, and have a fan blowing a slight breeze on them 24/7. I also use a 24/0 light schedule.
For seeds I start them in 32oz Uline Deli cups, and Promix BX. I then transplant them into 5 gallon grow bag containers, and veg for 60 days. And then transplant them into 20 gallon containers. I simply cut the grow bag away. I usually gas Im in an unfriendly state. I grow large plants because of plant numbers, but if it is a lower yielding strain I will use 4-6 -5 gallon container per 1000w HID. When I first started out I used a 1000w Metal Halide, but in the 90s switched to the Hortilux 1000w HPS because they added Blue to the light/HPS.
For huge yielding strain like Katsu Sour Diesel IBL, I either use 1 plant per 1000w HID and veg 60 days, or use 2 20 gallon containers, and veg 40 days. But 1 plant can easily take up a 4 x 4 area, and use the full 1000w HID. I usually get 18-24 oz per 1000w HID and minimal effort. Im lazy. I could probably get more if I topped them, and bent them, but you would also have to increase veg time, so it equals out in the end.
I also slightly shake my plants several times per day to induce more stress. This really makes the stalk, and branches stronger.
I Bend from the top, I usually go down about 20% down from the top of the plant, and bend there.
I bend my plants over and dont cut any bottom branches. I start bending them at a very young age. Weeks old. After the develop a strong root system. I try not to muck to much with the growing tip, as this can slow growth, but it can force more bottom growth, but I rely on the growing tip for more size. The plant will turn into a huge round hedge. But not all strains will respond to this technique. I also look for strains that have maximum stretch after inducing 12/12 flip.
If clones I start them in 32oz Uline cups, but when rooted, I plant them straight into 20 gallon containers of Promix BX. I root clones under 4ft Cool White Fluorescent.
I start feeding then a 10% strength solution as soon as they break the soil line. I feed every watering. This is if using chemical fertilizer of course.
I use Hydro Gardens
4-20-39
Calcium Nitrate-15.5-0-0
Epsom salts.
They are also mixed in this order.
I slowly increase the fertilizer as the plants grow. I dont change to any flowering fertilizer, I just slightly increase amount of the above fertilizers.
Also for an 8 weeks flowering strain, I will add Monopotassium Phophate-0-52-36 in weeks 3-4, and then boost the Epsom Salts in weeks 5-6. Week 7 gets a 25% reduction, and week 8 gets another 25% reduction. I also do not flush. I just cut back on the amount of fertilizer in weeks 7-8. If longer flowering varieties, I adjust accordingly.
