I have two pg260 and 4specctra 180 in a 5'x9' room why
leaves dieind
Back the spectras off, make sure that they are not angled directly down,add warm white light that faces directly down, and for Sagan's sake make sure that your plants aren't sitting still under the lights. I found the more leaf movement I had, the less burning occured. I have 435 watts of spectra, 165 watts of warm white lighting, and almost 100 watts of fans. These 700 watts cover a 5x6 area, so I'm satisfied. This lighting along, with mainlining and my "lean to" approach, has vastly increased my yields under spectras. Keep the lights at the same height through out flowering, and put the plants in when they are about 2.5' from the lights if they are 1.5-2x stretch.
Generally speaking red and blue light is highly efficient, and even the steepest gradient will still allow absorption. Chloroplasts containing the highest amounts of chlorophyll a and b are found closest to the surface of the leaf, the light is absorbed immediately. Too much excess red and especially blue *during flowering* will "over clock" the plant. She will respond by dropping leaves, starting mild fade, accelerated aging, and orange burns on the foliage.
He sold me the lights right as all the threads were finishing saying it was a terrible. He sold it to me as "green house supplementation", with a moderate discount. Having an X of blue rather than attempting to play sudoku with proper spectrum was the great down fall of the light, in my opinion. One part of the plant received tons of red, and another part would receive lots of white and blue light. The plants get confused about what the fuck is going on and eventually they just commit suicide. They all seemed to finish like 15 days early, compared to now, but the yield was pitiful.
I keep one 145watt spectra in a 30"x70" room about 3 feet above the canopy in a veg room. It works wonders.
Do not give up on LED lights, do give up on LED hype! Learn what and when your plants want it, and you will do well.
Also the white lighting only needs to be on 11 hours of the day, the first and last half hour can just be the red blue. Plants are used to this from nature and they really like it. Sunrise, sunset, and 200 plus days of no regrets.
Peace,
ILovePlants
P.S. Out of State until the end of the month, so no pictures of the set up unfortunately. So here's a picture of my favorite harsh led bred baby. She currently flowers about 16" from the spectra. Breeding helps with adaptation if you know what you are looking for. Day 25 in 12.5/11.5 in this picture.