When does light become too much light?

[Dire Squire]

I'm running 4x8 tents with 25 buckets per tent. Right now i'm using 3,000 watts per tent. Is this overkill?

Reason I ask is the warmer weather is making the temps get pretty high(low 80s). Thinking about removing a light from each tent.....

 

[sparkjumper]

I wouldnt say its too much light but if heats a problem you'll have to do something.I run 3 1K's in an 8 by 8 but I know I could use another even though I'm right close to 50 watts sq ft.If you can introduce co2 on a controller you can flower at 85-90F

 

[staank]

When plants receive too much light its called photoinhibition.
http://en.wikipedia.org/wiki/Photoinhibition

I'm not a scientist, but as I understand it the plant is hit with more photons than it can use relative to CO2/nutrients etc.

None if which has anything to do with HEAT, and it sounds you are really worried about heat not the amount of light.

You mention buckets in your tents, so I assume you are using some kind of hydro setup - I believe that if you keep the roots very cool the plants can handle higher temps. I'm not sure that low 80s qualifies as high heat for cannabis really anyway...

 

[antimatter]

Yes its overkill and you won't get 2 lbs per light but I don't see why it won't give you some benefit, just be aware that running high temperatures can cause the bud to fluff up and fluffy bud is no good, you need those cooler temperatures to harden up the buds. if your running CO2 than you can run higher.

 

[onahah]

Very nice

Very nice

Nice info with the fluff stuff antimatter. Im going to keep that in mind.

 

[Hydro-Soil]

Yes its overkill and you won't get 2 lbs per light but I don't see why it won't give you some benefit, just be aware that running high temperatures can cause the bud to fluff up and fluffy bud is no good, you need those cooler temperatures to harden up the buds. if your running CO2 than you can run higher.

I've heard it, in many places, that the CO2 won't help with the heat much. You'll still get fluffy buds (compared to CO2 in a regular temp setting). They'll be tighter than without CO2 but still far from optimum for your wattage.

Heat and ventilation are extremely important to nail down solid. I'll take a hit on lumens any day if it means manageable temps.

 

[sparkjumper]

I dont know where you heard that bro but if you're flowering at 1500PPM co2 at 75 degrees F,your results will be as if you grew without enrichment at all.Without the increase in temps and at least 50 watts sq ft,1500PPM may as well be 500PPM.I've been flowering blockhead for years at 85 F and sometimes a little higher and the buds are anything but fluffy.

 

[Hydro-Soil]

I dont know where you heard that bro but if you're flowering at 1500PPM co2 at 75 degrees F,your results will be as if you grew without enrichment at all.

At 100wpsqf, does this still hold true?

Everything I've read points toward CO2 having the most benefit in processing high intensity lighting. I've read more than once that CO2 is often, erroneously, suggested to help with heat. Often by hydro shop owners selling the equipment.

I'd love to see some real data on this.

 

[sparkjumper]

Anything over 50 watts sq foot will benefit from 1500PPM co2,providing the temps are higher.Its not that co2 helps with heat,its that co2 enrichment is ineffective without higher tempertaures.If you are flowering at 85 F and you cant do anything to bring down temps then introducing 1500PPM co2 would definately be beneficial,so it works backwards too I guess.

 

[antimatter]

Anything over 50 watts sq foot will benefit from 1500PPM co2,providing the temps are higher.Its not that co2 helps with heat,its that co2 enrichment is ineffective without higher tempertaures.If you are flowering at 85 F and you cant do anything to bring down temps then introducing 1500PPM co2 would definately be beneficial,so it works backwards too I guess.

A Co2 tank yeah, but as soon as you add a Co2 burner your looking at increases in humidity and temperatures, its pretty much a given that if you got a Co2 burner you better have a good dehumidifier/Air Conditioner. Ive always wondered how outdoor plants handle those 100 degree temperatures is it because theres more Co2 outside? ive read with global warming the increases in temperatures are outweighing the increased Co2 emissions in the atmosphere causing crop yields to be lower. I would say no higher than 80-85 F indoor running Co2 but without running 72-76 F 78 max.

 

[hoosierdaddy]

Bringing global warming into the mix is making a mockery of our sport.

OD plants can handle things because the root zones are cooler than the ambient temps the greenery sees. Same with indoor plants. Keep the root zone cool, and they can thrive very well in 90 deg or more temps...providing the humidity level is also proper.

 

[antimatter]

Bringing global warming into the mix is making a mockery of our sport.

OD plants can handle things because the root zones are cooler than the ambient temps the greenery sees. Same with indoor plants. Keep the root zone cool, and they can thrive very well in 90 deg or more temps...providing the humidity level is also proper.

Who doesn't love global warming I feel sorry for whoever has to live on this planet in a hundred years.

On a less serious note, it interesting how if it was 90 degrees indoors the plants would hate it but outdoors not so, I never thought to think the root zone temperatures had something to do with that because I see people growing in pots outdoors also handling those extreme temperatures.

 

[Hydro-Soil]

When plants receive too much light its called photoinhibition.
http://en.wikipedia.org/wiki/Photoinhibition

I'm not a scientist, but as I understand it the plant is hit with more photons than it can use relative to CO2/nutrients etc.

None if which has anything to do with HEAT, and it sounds you are really worried about heat not the amount of light.

You mention buckets in your tents, so I assume you are using some kind of hydro setup - I believe that if you keep the roots very cool the plants can handle higher temps. I'm not sure that low 80s qualifies as high heat for cannabis really anyway...

Sorry I missed where you'd already stated this Staank. The heat/CO2 thing is an age old misconception.

As for hydro in high heat areas (+75F) Ebb&Flow or drip is much better for any area that has higher heat temps. Try not to run DWC/SWC in those situations unless you like a lot of extra work and spending a lot of cash on chillers and air pumps.

 

[sparkjumper]

HS could you explain what you mean about the co2/heat thing being an age old misconception?I think people are going to get real confused at all these conflicting statements.Hell I know I am and I'm making most of them lol

 

[Hydro-Soil]

HS could you explain what you mean about the co2/heat thing being an age old misconception?I think people are going to get real confused at all these conflicting statements.Hell I know I am and I'm making most of them lol

Np

Basically all the studies I've read, such as what Staank linked to, say that CO2 usage by the plant is directly linked to light intensity.

CO2 equipment is very expensive and a great retail item for a hydro shop to sell and, most, of the time the people that have heat problems, also have extreme light intensities. Adding CO2 makes things 'better'.

The issue is that improving the ventilation would be cheaper and have nearly the same effect, unless the lights are so close they're bleaching out the leaves.

Over the years, people have begun to erroneously tie CO2 with helping heat stress. True, CO2 is more effective at higher temps than 75F but that's in no way an indicator that it works 'better' at temps over 85F.

Be smart. Spend your money on ventilation and controlling heat before you spend cash on CO2.

 

[antimatter]

Np

Basically all the studies I've read, such as what Staank linked to, say that CO2 usage by the plant is directly linked to light intensity.

CO2 equipment is very expensive and a great retail item for a hydro shop to sell and, most, of the time the people that have heat problems, also have extreme light intensities. Adding CO2 makes things 'better'.

The issue is that improving the ventilation would be cheaper and have nearly the same effect, unless the lights are so close they're bleaching out the leaves.

Over the years, people have begun to erroneously tie CO2 with helping heat stress. True, CO2 is more effective at higher temps than 75F but that's in no way an indicator that it works 'better' at temps over 85F.

Be smart. Spend your money on ventilation and controlling heat before you spend cash on CO2.

Co2 is great for people who have a handle on there heat and have a AC/Dehumidifier that kills, if you got heat problems and you think adding a Co2 a Burner is gonna fix heat problems your in for a surprise. I think its a better investment to just start with Co2 and a sealed room right off the bat with Cooled Hoods, if its just a couple lights don't bother but if you got 9kw running well that 20-30% increase in yield adds up.

Heres a thread for anyone that wants to implement Co2, gives you the ins and outs. http://www.icmag.com/ic/showthread.php?t=48203&highlight=CO2

 

[sparkjumper]

Adding co2 was the best thing I ever did for sure.It's true you must have temp/humidity control and at least 50 watts sq. ft. but its not really that difficult.I run 3 1K vertizontals in an 8 by 8 which are uncooled and use a 12K BTU window AC.A 45 pint dehumidifer tops it off along with a wall mounted oscillating fan.Its a matter of expense more than difficulty I'd say.One thing I learned for sure is that a co2 controller is a must.If you cant keep enriched PPM to fluctuating more than 200PPM it doesnt work worth a shit.I know this from using a cyclestat for a long time.It controls frequency and duration of burn according to room size not taking into account the number,size or stage of the plants in the room.You go by cu. ft. of room size only.Worthless

 

[Philosophelon]

I think that if one is already running enough light that CO2 will be effective, and temps are in the low 80's, it is more sensible to add CO2 than remove some heat. As you already have enough light intensity to realize an increase in yields with CO2, why not just add CO2 to increase yield, and then an ambient temp in the low 80s is beneficial anyway.

Put another way, you have two options:

1) Reduce ambient air temp to low to mid 70s, and get a small increase in yield because you are now running ideal temps for normal atmospheric CO2 levels.

2)Add a CO2 tank to supplement CO2 levels, leave temps where they are, and get a relatively large increase in yield because your plants are now using all available light.

 

[sparkjumper]

YOU FORGOT THE CONTROLLER damn.If your not going to have it on a controller whether tank or burner you will get normal results!I swear I know all to well I wasted a lot of time and I dont see why others should.I know people use the formula's and think they are getting results,I sort of did.Then I bought a 10 pak of syringe type co2 testers and saw where I was at throughout the day.Fuckin pitiful I tells ya.You cant have those fluctuations

 

[antimatter]

YOU FORGOT THE CONTROLLER damn.If your not going to have it on a controller whether tank or burner you will get normal results!I swear I know all to well I wasted a lot of time and I dont see why others should.I know people use the formula's and think they are getting results,I sort of did.Then I bought a 10 pak of syringe type co2 testers and saw where I was at throughout the day.Fuckin pitiful I tells ya.You cant have those fluctuations

I was under the impression that if you didn't have a controller than you kinda missed the point lol