If watering more often, should I cut down on nutes (ppm) ?

I've been following a feeding schedual that has worked very well so far, but now I have done something that few of us have, I've made an upgrade on my lights which has increased the light intensity to the extreme. So far it was one 1150W papillon e-light per 5x5 feet (1.5 x 1.5 meters), but now it is the same amount of light per 4.17 x 4.17 feet (1.27 x 1.27 meters) PLUS additional interled that will be put under the crop. In other words it will be 723w per square meter + leds.

With this much light it is VERY easy to kill the plants fast, so it would be essential to keep humidity as high as recommended in VPD chart (around 80%) at 32 degree celsius along with 1500ppm of CO2.

If all conditions will be ideal, they will grow superfast and they will also drink lots of water. I'm at the moment 1.5 weeks into flowering and about to dim from 1000w to 1150w (superlumens), but before I'm going to do that I want to tell you what my concern is.

I'm asking you to help me to understand what should be done to the strenght of nutes I'm giving them in the water? So far I've managed to water them every two days in coco (1 day off), but I predict it's going to be every day now. If they drink so much, is it logical to cut down on nutes a bit or should I keep PPM the same?

Helmut79 said:

I've been following a feeding schedual that has worked very well so far, but now I have done something that few of us have, I've made an upgrade on my lights which has increased the light intensity to the extreme. So far it was one 1150W papillon e-light per 5x5 feet (1.5 x 1.5 meters), but now it is the same amount of light per 4.17 x 4.17 feet (1.27 x 1.27 meters) PLUS additional interled that will be put under the crop. In other words it will be 723w per square meter + leds.

With this much light it is VERY easy to kill the plants fast, so it would be essential to keep humidity as high as recommended in VPD chart (around 80%) at 32 degree celsius along with 1500ppm of CO2.

If all conditions will be ideal, they will grow superfast and they will also drink lots of water. I'm at the moment 1.5 weeks into flowering and about to dim from 1000w to 1150w (superlumens), but before I'm going to do that I want to tell you what my concern is.

I'm asking you to help me to understand what should be done to the strenght of nutes I'm giving them in the water? So far I've managed to water them every two days in coco (1 day off), but I predict it's going to be every day now. If they drink so much, is it logical to cut down on nutes a bit or should I keep PPM the same?

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In nature does the sun shine under the crop or does it shine on the top and side?

I dont care what any vpd chart says but 80% is out there I would never run that high unless I wanted pm and br.

that high of a co2 seems excessive and a waste

Running in super lumen I wouldnt do that unless I wanted to lessen the life of my bulbs or it was on the last two weeks of me using that bulb ever.

Smaller the plant smaller ppms bigger the plant bigger ppms sick plant lower ppms healthy plant higher ppms. Excessive salts restrict plant growth.
microbes are your friend.
GL.

Helmut79 said:

I've been following a feeding schedual that has worked very well so far, but now I have done something that few of us have, I've made an upgrade on my lights which has increased the light intensity to the extreme. So far it was one 1150W papillon e-light per 5x5 feet (1.5 x 1.5 meters), but now it is the same amount of light per 4.17 x 4.17 feet (1.27 x 1.27 meters) PLUS additional interled that will be put under the crop. In other words it will be 723w per square meter + leds.

With this much light it is VERY easy to kill the plants fast, so it would be essential to keep humidity as high as recommended in VPD chart (around 80%) at 32 degree celsius along with 1500ppm of CO2.

If all conditions will be ideal, they will grow superfast and they will also drink lots of water. I'm at the moment 1.5 weeks into flowering and about to dim from 1000w to 1150w (superlumens), but before I'm going to do that I want to tell you what my concern is.

I'm asking you to help me to understand what should be done to the strenght of nutes I'm giving them in the water? So far I've managed to water them every two days in coco (1 day off), but I predict it's going to be every day now. If they drink so much, is it logical to cut down on nutes a bit or should I keep PPM the same?

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Cpl things here to expound on.

As far as using 1500 ppm of gas....You don't have enough light intensity to actually use that much gas effectively..... The max usable for you (and just about anyone else) is 1300 ppm, more like 1200 but I bet you want to push it? Run your gas at 1200 ppm and you are correct in using the VPD chart while gassing......I would hope like hell you have an environmental controller turning off and on the cooling and exhaust systems automatically.

It should be noted that effective gas ppm use is directly related to the available light intensity.... Not many bother to say that it's next to impossible to effectively run 1500 ppm..... With any 1K HID light...Your stuck at around 1200 ppm... Adding that last 15% in super lumens will not carry you to anywhere near effective 1500 ppm use.

You see the increase in intensity vs. Gas ppm is like a bell curve....The amount of light needed to effectively utilize any increase in gas ppm's. Is an exponential amount...

Under lighting is not as effective as you think..... Don't bother. Lower buds do not need lighting to grow. It does help with them ripening. Simply harvest in "layers" or do a "staggered harvest".
Harvest the mains and let the lowers sit about 2 weeks....Harvest the rest.

As far as any reduction or increase to watering/feeding.... That's called "dialing in". Every time you change something in your environment. You likely will have to make a feeding change....
Once you have your dial in for the strain your running. Always run that...

Strains run different.

Some like lots of feeding

Some like less K

some like less N

some more N

Some are Mg hogs.

Some are so fussy, I find them not worth the work....

"To even make 1300 ppm usable by the plant... You would need to deliver 48,240 lux (I use lux as it's easier to understand then mol). A 1k HPS does not deliver that amount of light energy.....I listed 1300 ppm as a high end limit, by lighting limitations."

https://www.rollitup.org/t/should-nutrients-ppm-be-increased-with-co2-enrichement.952392/

Hey, Dr. Who

I measured the light intensity of my crop with 2 different luxmeters and got an average of 55,000 - 65,000 lux around the whole crop.. and this is with only 1000W each lamp. I haven't dimmed to superlumens yet (1150w). My lightning plan has been designed by one scientist whose work is basically all about lightning calculations and design. They grow marijuana legally in Germany in controlled environment just for scientific purposes. Harvest goes into termination by police

I'm following his lightning plan atm, but I'm a bit scared to dim to superlumens just yet. Want to be sure not to burn it. Is there some kind of chart which shows how much lux is needed for certain amount of Co2 ppm?

Spurr says it should not be over 1200. He seems to know what he's talking about:

The facts about CO2 ppm: don't use 1,500!
High,

I haven't posted much lately, but I thought this topic was important enough to write a thread. I have written about this topic quite a lot in the past, but I have never made a thread just for this topic.

My goal: to try and kill the myth that 1,500 ppm CO2 is ideal. I want to get it known in the cannabis world, that it's important to not use > ~1,100-1,200 ppm CO2.

In short, the claim that 1,500 ppm CO2 is ideal for cannabis is total hogwash. I challenged anyone a while ago to find a single scientific study showing 1,500 ppm is ideal for C3 flowering plants, or even just to find the reasons why it's claimed 1,500 ppm is ideal in the cannabis world. I assume the myth (yet another!) came from the liked of Ed Rosenthall or George Cervantes or Mel Frank, etc.

If there is interest in the 'whys' I can explain why it's important to not use > 1,200 ppm, ideally we would use ~1,000-1,100 ppm. The effects from "super-optimal" CO2 concentrations range from reduced rate of photosynthesis, to reduced yield, reduced root growth, reduced stomatal openness, increased photorespiration, etc. In other words, nothing good.

The reason why we should ideally use ~1,000 ppm, is for most C3 species (and C4 I think), CO2 "saturation" occurs at ~1,000-1,100 ppm. That means more than ~1,100 ppm (up to 1,200 ppm) isn't going to help the plants, it's only going to waste CO2 and hinder plants if CO2 is about > 1,200 ppm.

The reason why we should ideally use < 1,200 ppm CO2 is the effect high (super-optimal) CO2 has on "Rubisco activase", the substance that turns inactive "Rubisco" into active Rubsico. At CO2 > ~1,200 (and temp > ~89'F) Rubsico activase is inhibited, which in turn inhibits conversion of inactive Rubisco into active Rubisco. And active Rubisco is needed for high rate of photosynthesis, which in turn leads to high growth rates and high yield, etc.

So, to sum up: It's important to keep CO2 below ~1,200, and to be safe and most efficient, keep CO2 at ~1,000 ppm. Night time CO2 should be < ~500 ppm, unless one is trying to reduce dark respiration and stretch, then upwards of 750 ppm can be used for short periods (otherwise leaf chlorosis can set in)

I can fully cite all those claims, if anyone wants to read the academic lit.

Bernie420 said:

In nature does the sun shine under the crop or does it shine on the top and side?

Click to expand...

I am atm doing side by side experiment on those interleds that will go under the crop (or maybe its more accurate to say into the crop) and soon I will get to see the difference in results. Then I will know if the cost of led lamps is worth it or not.

Bernie420 said:

Running in super lumen I wouldnt do that unless I wanted to lessen the life of my bulbs or it was on the last two weeks of me using that bulb ever.

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Can you please explain further? Do you think superlumens really damage the bulb so much? Maybe it's different with double-ended bulbs? I am using a Philips E-papillon 1000W with double-ended bulbs in it. It lasts many times longer than traditional bulbs, just so you know. Let me know what you think.

Helmut79 said:

With this much light it is VERY easy to kill the plants fast, so it would be essential to keep humidity as high as recommended in VPD chart (around 80%) at 32 degree celsius

Click to expand...

Yikes

Dr. Who said:

I would hope like hell you have an environmental controller turning off and on the cooling and exhaust systems automatically.

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My exhaust starts working at the moment when lights turn off, but if the lights are on, there is no exhausting at all. The cooling is made by an AC unit. But yes, it all happens automatically. Finally I'm there with my life

Dr. Who said:

It should be noted that effective gas ppm use is directly related to the available light intensity.... Not many bother to say that it's next to impossible to effectively run 1500 ppm..... With any 1K HID light...Your stuck at around 1200 ppm... Adding that last 15% in super lumens will not carry you to anywhere near effective 1500 ppm use.

Click to expand...

What do you think would be the light intensity needed to use up 1500ppm of co2?

Dr. Who said:

Under lighting is not as effective as you think..... Don't bother. Lower buds do not need lighting to grow. It does help with them ripening. Simply harvest in "layers" or do a "staggered harvest".
Harvest the mains and let the lowers sit about 2 weeks....Harvest the rest.

Click to expand...

Harvesting in layers is quite a good idea, although I'm not sure if its worth it compared to using that extra 1 or 2 weeks to starting a new round with new fresh plants. What you think?
Another thing is that you also say under lighting is not worth it. I guess you may be interested to see the difference in my final results with one row of plants grown with inter-leds and other row without. Yes?

Helmut79 said:

I am atm doing side by side experiment on those interleds that will go under the crop (or maybe its more accurate to say into the crop) and soon I will get to see the difference in results. Then I will know if the cost of led lamps is worth it or not.
Can you please explain further? Do you think superlumens really damage the bulb so much? Maybe it's different with double-ended bulbs? I am using a Philips E-papillon 1000W with double-ended bulbs in it. It lasts many times longer than traditional bulbs, just so you know. Let me know what you think.

Click to expand...

Sure can.
You have a car and need to drive across country and this trips takes two months. On the dash your tach say's that 1k to 5k rpm is in the safe zone but your tach goes to 7k rpm's but that's in the red zone. You decide to drive with the engine at 6800 rpm the entire time. What do you think is going to happen?

I get your point, but i find it hard to believe that it's so harmful as you describe. I get the feeling that you are exaggerating a bit. Nevertheless you make me worry and I want to make sure I haven't already fucked up the bulbs. It should be easy to make sure by measuring lumens?

Helmut79 said:

I get your point, but i find it hard to believe that it's so harmful as you describe. I get the feeling that you are exaggerating a bit. Nevertheless you make me worry and I want to make sure I haven't already fucked up the bulbs. It should be easy to make sure by measuring lumens?

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Just search super lumens and there are plenty of forums about it if you dont think its a bad thing for your bulbs. Call the bulb manufacturer and post what they say.

BTW the car blew up in the middle of nowhere two weeks into the trip and we didnt have any weed.

Helmut79 said:

What do you think would be the light intensity needed to use up 1500ppm of co2?

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I don't have my old calculated chart near but, If I remember right (I know I'm close +/- a cpl K) it's like 84,000 lux..

Helmut79 said:

If there is interest in the 'whys' I can explain why it's important to not use > 1,200 ppm, ideally we would use ~1,000-1,100 ppm. The effects from "super-optimal" CO2 concentrations range from reduced rate of photosynthesis, to reduced yield, reduced root growth, reduced stomatal openness, increased photorespiration, etc. In other words, nothing good.

Click to expand...

You overcome this problem by running high temps and high RH, while running gas at around 1200 o 1300. About 89-90 temps and 80+ RH.

Dr. Who, from where should this 89-90F be measured?
1) In the light on top of canopy?
2) Or in shade inside of canopy?

There is also leaf temperature which can be measured with infrared thermometer as I can understand.

How to understand it accurately? Exactly from where?

Helmut79 said:

Dr. Who, from where should this 89-90F be measured?
1) In the light on top of canopy?
2) Or in shade inside of canopy?

There is also leaf temperature which can be measured with infrared thermometer as I can understand.

How to understand it accurately? Exactly from where?

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No

In the light (with radiant heat included) on top of canopy + in the shade inside of canopy = and take the average?

No to what? Maybe you can say more than that.

Helmut79 said:

In the light (with radiant heat included) on top of canopy + in the shade inside of canopy = and take the average?

No to what? Maybe you can say more than that.

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No idea why idiots here want to place thermometers under lights let alone why they want to ascertain a canopy temperature but you are following bad advice and fools by doing that.

The thermometer is placed in a position where it is shaded from all indirect and direct light, thats not the canopy by a long shot and you confuse the need to read air temps and not light radiation.

This should be basic 101 simple first thing you learn.... On weed sites science takes a back seat to ego wannabe growers who although can grow know dank all about how to grow.

Hope that helps, dont be a troll once you learn to grow like the like the recent click here giving advice