When to increase lights?

Cana-bliss

Cana-bliss

Active Member
I've got 12 x EBgen2 two foot strips in a 3x3 powered by an hlg 320 in parallel. Right now I'm 2 weeks into flower lights, about 12" from canopy, temps stable at around 75f (23-24C) with humidity around 62%. I've got an inline DROK digital power meter between the strips and driver so as I adjust it I can see actual power draw (volts/amps/watts) in real time. Right now I can only run the light at 170 watts. Anytime I try increasing the power (5 watt increments) the plants get droopy and start having purple stems on the leaves. When do you guys increase your lights output on your plants? I can run mine up to 270 watts but can't see the plants taking it at this point.
 
Airwalker16

Airwalker16

Well-Known Member
Cana-bliss said:
I've got 12 x EBgen2 two foot strips in a 3x3 powered by an hlg 320 in parallel. Right now I'm 2 weeks into flower lights, about 12" from canopy, temps stable at around 75f (23-24C) with humidity around 62%. I've got an inline DROK digital power meter between the strips and driver so as I adjust it I can see actual power draw (volts/amps/watts) in real time. Right now I can only run the light at 170 watts. Anytime I try increasing the power (5 watt increments) the plants get droopy and start having purple stems on the leaves. When do you guys increase your lights output on your plants? I can run mine up to 270 watts but can't see the plants taking it at this point.
Click to expand...
Purp stems are part of led
 
InTheValley

InTheValley

Well-Known Member
You get purple stems because the lack of calmag. If your spectrum is high reds driven, like alot are driving today, the rate of photosynthesis is higher, which demands more calmag and potassium, as with high temps. When temps are higher, the leafs internally get hotter, so you may see heat stress, or droop. and then browning, leaf tip curl up, and rust looking, because the leaf is dryin out internally.

If your using RO water, its necessary to add 200-250PPMs of calmag straight away, and use it thru week 5 of flower.
 
R

Ryante55

Well-Known Member
Cana-bliss said:
I've got 12 x EBgen2 two foot strips in a 3x3 powered by an hlg 320 in parallel. Right now I'm 2 weeks into flower lights, about 12" from canopy, temps stable at around 75f (23-24C) with humidity around 62%. I've got an inline DROK digital power meter between the strips and driver so as I adjust it I can see actual power draw (volts/amps/watts) in real time. Right now I can only run the light at 170 watts. Anytime I try increasing the power (5 watt increments) the plants get droopy and start having purple stems on the leaves. When do you guys increase your lights output on your plants? I can run mine up to 270 watts but can't see the plants taking it at this point.
Click to expand...
75 is to cold the plants can easily handle all the light you have the plants just get stressed I stressed my new clones out last week they were totally purple didn't change anything with the feeding just let them get used to the light all new growth is nice an green. I've never used calmag growing with led for over 4 years. I get really confused when people have so much trouble I think people like to try to find something to blame when their plants don't look good. I personally blame myself not the lights or some other crap. if you feed a nice balanced diet and up the light they should be fine they will probably be stressed for a few days then explode with growth its like getting a sunburn then peeling to a nice tan.
 
Cana-bliss

Cana-bliss

Active Member
My tap water is 120 ppm and I feed 2 tsp/gal of GO cal-mag with every feed. Since they've been showing flowers I've been slowly increasing the bloom mix as well. Plants are super happy until I turn the lights up, I tried leaving them for a week at 180 watts and they just stayed sad and droopy. I did have an exhaust fan running with the higher wattage to keep the temps in the 23c-24c range so I'll try increasing the temp with the watts to see if I get a more favorable environment. I'm def not running 70% humidity in flower though, not a big fan of smoking mold.
 
R

Ryante55

Well-Known Member
Cana-bliss said:
My tap water is 120 ppm and I feed 2 tsp/gal of GO cal-mag with every feed. Since they've been showing flowers I've been slowly increasing the bloom mix as well. Plants are super happy until I turn the lights up, I tried leaving them for a week at 180 watts and they just stayed sad and droopy. I did have an exhaust fan running with the higher wattage to keep the temps in the 23c-24c range so I'll try increasing the temp with the watts to see if I get a more favorable environment. I'm def not running 70% humidity in flower though, not a big fan of smoking mold.
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You will learn vpd someday I used to think like you but vpd really does work. I know you think the light is to much but it really isn't most people run 300+ watts in that space and you say your plants can't handle 180? Something isn't right
 
Cana-bliss

Cana-bliss

Active Member
Yeah I'm def not deficient in anything plants are real happy and vibrant. So when I crank up the wattage their unhappiness is very noticeable (definitely an environment issue). @RedStoolSample I'm under the impression that raising the light and increasing the wattage has no effect as you need more wattage when an LED is further from the plants. I did increase the wattage to 185 watts today without turning on the exhaust fan temps have gotten up to about 26C and all seems well so I'll start rolling with the increase temp idea for a bit and see how it goes. If the general consensus is that raising the light and cranking it is better then having it close with a lower wattage then I'll try that as well.
 
Renfro

Renfro

Well-Known Member
Balance. When light is more intense the temperature needs to be warmer, co2 levels higher and they will drink faster and need stronger feed.

CO2 is a limiting factor unless you are adding CO2. In that case temperature needs to be warmer to increase their metabolic rate. Then they will drink more water and may desire a stronger feed (let the plants tell you).

The VPD chart is a good way to achieve a balance between temperature and humidity, then you need to account for CO2 levels (that determines target temperature). The amount of light that you use will be dependent on co2 levels / temperature.

So you need to find a doable balance in your situation. does any of that make sense? I am pretty high.
 
delstele

delstele

Well-Known Member
I raised my temps up 83 - 85*F with the suggestions I have read here seems to be working for me. I was seeing a bit of slow growth at first upped the nutes, started running my room a bit hot from passed temps plants took off like a rocket..
 
Cana-bliss

Cana-bliss

Active Member
Yeah I'm adding C02 through fermenting 2 1/2 cups sugar in a gallon of water per week with some ec-1118 wine yeast, works pretty damn good. So it looks like attempting to keep the temps lower was my issue. I'll continue to allow the temps to climb while increasing the wattage to see how that works.
 
Cana-bliss

Cana-bliss

Active Member
Renfro said:
And use a VPD chart to match humidity to the temperature.
Click to expand...
I've got this one taped on the inside of my door and just try to stay in the middle of the suggested numbers. I know it's not as precise as some would require but I'm sure it's close enough.
VPD Chart.jpg
 
1

1212ham

Well-Known Member
Cana-bliss said:
Yeah I'm adding C02 through fermenting 2 1/2 cups sugar in a gallon of water per week with some ec-1118 wine yeast, works pretty damn good. So it looks like attempting to keep the temps lower was my issue. I'll continue to allow the temps to climb while increasing the wattage to see how that works.
Click to expand...
FWIW, I've run EB Gen-2 within 2-3 inches. Girls are quite happy at 30C without CO2.
Hmm... your VPD chart shows a lot of humidity, what's the source? Here's a popular one.

http://www.just4growers.com/media/23637/vpd_1degree.gif
http://www.just4growers.com/stream/...-deficit-the-hidden-force-on-your-plants.aspx
 
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InTheValley

InTheValley

Well-Known Member
Lets get this figured out for you today,ok?

There is alot of things said in this thread about many things, but something that has to be known is, VPD is great, BUT, not all strains follow the same VPD. Its necessary to take notice when the leafs pray, and write the RH% and Temp down on paper, and THAT is YOUR STRAINS VPD. That is the number you need to work with till 4 weeks before chop, then you want to lower RH%, and temp.
 
InTheValley

InTheValley

Well-Known Member
Now, with LEDs because they differ from HPS, we need to use LUX, and i know i know, LUX means nothing to humans or whatever people say, but what we need to know is the INTENSITY of the light.

When you veg, you should be vegging with under HALF of available INTENSITY. And using the most INTENSITY after the stretch is done in flower, then you would give her the max INTENSITY available.

So, lets take your light for instance, and u have 270 available watts to use. But that doesnt say a whole lot, because we dont know the intensity of the light, and the distance you can use that light at.

Which is why u need a LUX meter. So, ur using strips, which is a great way to get the same consistency over your canopy, so it makes it easier to figure this out.
 
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