Chip Green
Well-Known Member
Hands down, the best LED for overall yield, are the ones I built for my rooms...
I aint tellin what they are neither.....
I aint tellin what they are neither.....
Best LED for overall yield
- Thread starter pokerpro451
- Start date
Airwalker16
Well-Known Member
What are you implying causes red stem in days old seedlings?
OLD MOTHER SATIVA
Well-Known Member
thank you.iam sure you picked up all the knowledge by yourself ...
we will all continue to help anyone..it's what the forum is for..
Chip Green
Well-Known Member
Let's not forget about extreme sarcasm, fueled by Belgian Ales, posted on randomly chosen threads....
In retrospect, I believe my intended point may have been, that too many variables are in play to determine the "best" LED....
InTheValley
Well-Known Member
lack of mag from the LED eating it up faster, Closer the light, more mag needed. Thats what Ive come to conclude, 1 more run to certainfy my theory,lol.
BCBLondesLEDGrowLights
Well-Known Member
can be anything stressful, too much light, too cold, etc
pokerpro451
Member
No one likes an A-hole.
pokerpro451
Member
You know I've tried really hard to get fluence to answer my questions and they have ignored me. On IG. Pretty shitty costumer service to someone willing to drop 10k in your equipment. Timber has been amazing. I'm just not sure they are efficient enough to ever do 2 grams per watt.
Humple
Well-Known Member
Have you looked at the options from HLG, ChilLED, Amare, Scynce, or Progrowtech? (I'm sure I'm missing some.)
BCBLondesLEDGrowLights
Well-Known Member
Regarding your issue about most ppf and ppf/watt. Just buy one extra 340 watt bcb game changer per row and you'll spend less, and have the most ppf, and hit your target.
Randomblame
Well-Known Member
Depends on how much watt you use per sft. Pretty sure with 25-30w/sft(500-600μMol/s/m²) and a high yielding strain you can hit that 2g's per watt. Timber is top!!!
pokerpro451
Member
I'd like to average about 900umols per sq ft because I use C02
Randomblame
Well-Known Member
Then 35-40w/ft² is the way to go. 560-640w in a 4x 4' area and 315-360w for a 3x 3'. You could even get up to 1000 and more with less distance. Optimal distance depends at which height you have good uniformity. A lux meter app or a cheap lux meter(12$, e3ay) works great. I usually try to get 80% uniformity for good and even coverage.
And keep an eye on your VPD! Air tends to dry out under strong LED light!
Use the chart below or get a controller where you can set VPD separately.
hybridway2
Amare Shill
The center of each color of the graph is our goal VDP?
Ex.:
Just quick scribble but you understand, right?
dstroy
Well-Known Member
More of a guide for you to use, everyone's setup is different so there is no ideal number for everyone. If your plants don't look good, adjust and observe.
Randomblame
Well-Known Member
Yeah, depends on ambient temps(left scale)!
The higher the ambient temperature the lower the relative humidity.(higher VPD)
Warm air can hold more water like cool air for that reason it's called relative. When warm air gets mixed with cold air and cools down it starts getting cloudy and with even more cold air into the mix its raining!
But when cold air warms up relative humidity goes down. The air could hold more water but without additional water (humidifier) the relative amount of water inside the air gets lower.
When the light goes on with 20°C and 60% and the air is warmed up to 30°C within the next hour there is still the same amount of water but because air can hold more at 30°C the RH is only 40-45% or so.
So at first look at the left temps scale and go to the right according to the current plant stage, germination, week of veg or flower. The older the plant the more VPD they can handle. 0,8-1,2kpa are usually okay in veg and 1,2-1,6kpa in flower while the 1,6 is only meant for the very last few weeks when the tops starts to fatten up.
Randomblame
Well-Known Member
Yeah, as mentioned earlier, there are more ways to work with a low humidity level. A lower nutrient strength for instance. When the VPD is 20% too high lower the ppm's also by 20%! The plants can take up 20% more water without getting more nutes. The relative nutrient uptake will stay the same and therefor you can expect the same yield and healthy looking plants.
hybridway2
Amare Shill
Thanks you!
It's all starting to come together.
The above chart is a flower chart?
I have others youve posted with veg weeks.
Raised humidity to 55-62% in flower & the plants freaking stabilized. Couldn't even believe it.
Temps don't get that low if I can help it so now I see.
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Randomblame
Well-Known Member
Nope, its for germination, veg and flowering stage. You start with very high humidity and seedlings(0,8kpa), increase it slowly in veg (up to 1,2kpa) and finish the run with with the highest VPD(up to 1,6kpa).
Blumat(a german company) has a tensiometer to measure the water soil potential(20-40$ am4zon). When the VPD is for instance 1,2kpa you have the same tension on the other side at the roots. But this tensiometer(a simple 6" plastic tube, a 2" clay cone(as membrane) to put in the soil and a little meter on top, which is connected to the membrane) measures in mbar. But its pretty easy cuz 80 - 120mbar is the same like 0,8 - 1,2kpa.
This is the easiest way to keep an eye on the true VPD simply by measuring the the suction tension inside the soil.
Leaves and roots are connected and there is a capillary effect. What goes out thru the leaves must go in thru the roots.
But a tensiometer works only with soil, coco and rockwool cubes; no DWC, no clay pebbles!