you asked about light, LED?
get this app
Professional light intensity (lux) meter for your android device.
play.google.com
Clones and seedlings: 2,000β4,000 lux and doesnt matter so much
Vegetative growth: 15,000β30,000 lux start at 20, watch plant. you are looking for leaves pointed up "praying"
Flowering: 45,000β110,000 lux the upper end needs co2. try starting at 65,000, watch and adjust
as for how high, try this (this is REAL wattage, so on an led look at actual wattage, an led that says 1000 is normally only 100w maybe 150w. no real standard.
- 5β to 11β for 150W lights
- 6β to 13β for 250W lights
- 8β to 19β for 400W lights
- 9β to 25β for 600W lights
- 11β to 31β for 1,000W lights
the key to it all is to spend the time watching them and adjust as they tell you