George2324
Well-Known Member
Raising the lamp would be the same as just dimming them further.Forget this! 12-15inch is way to less distance at such intensity and you will end up with getting massive bleaching. Get a cheap lux-meter and try to spread the light as much as possible for an even canopy coverage. Above 65.000lx(ca. 1.000μMol/s) it is really easy to get bleaching, also if you feed your plants with additional CO². Äquatorial sativas can handle intense light much better as a dutch outdoor indika for temperate climazones. So it's also strain dependent.
I would recommend to start with 24-30" and let the plants grow untill you see first signes of stress. Than rise the lamp a bit and keep that distance for the whole grow!
If you can dim lights I don't see why anyone would raise lights when they can dim.
Reason I want to attemp to get them as close as possible is that I want nice long colas.
If you dim instead of raise them then you will be saving electricity