Am I overkilling it on lights?

[Dank Bongula]

^Just put some screen material over that outlet so bugs don't come crawling straight into your tent

 

[crimsonecho]

I like that idea but how do I go about getting 30w/ft2?

4x4= 16
16x30= 480
480/3= 160

so you can run all 3 fixtures at 160w and get 30w ft2

 

[Dank Bongula]

4x4= 16
16x30= 480
480/3= 160

so you can run all 3 fixtures at 160w and get 30w ft2

My current run is only at 17w/sqft. Sensitive bitch.

 

[crimsonecho]

My current run is only at 17w/sqft. Sensitive bitch.

not all of them thrive under high wattage but i ran about 450-480w in 4x4 for the last years and found it to be a perfect middle ground for the sativas and hybrids i like growing. with co2 i can push it higher but no co2.

17w is really low though, are the roots ok? do you run cobs or smds?

 

[Stunx]

Y'all are the best, I'm going to do both. The new AC I'm getting actually used less power than this old 6,000 BTU I'm currently using, so it's going to be win across the board

 

[Dank Bongula]

not all of them thrive under high wattage but i ran about 450-480w in 4x4 for the last years and found it to be a perfect middle ground for the sativas and hybrids i like growing. with co2 i can push it higher but no co2.

17w is really low though, are the roots ok? do you run cobs or smds?

I normally run my 300Lrspec at max but for some reason this last run of mephisto hybrids just did not like it. Down to just one last plant (double grape) before I shut down for summer. It has been praying to the light pretty much since day one

 

[crimsonecho]

I normally run my 300Lrspec at max but for some reason this last run of mephisto hybrids just did not like it. Down to just one last plant (double grape) before I shut down for summer. It has been praying to the light pretty much since day one

interesting how are your yields at that low wattage?

 

[Lenin1917]

My current run is only at 17w/sqft. Sensitive bitch.

autos?

 

[Lenin1917]

With leds watt/sqft is generally a shitty metric. My 480w leds are only 30w/sqft but I hit a dli of 60 on 12/12 umol/w is the metric you want to look at some of these new lights are super efficient.

 

[crimsonecho]

With leds watt/sqft is generally a shitty metric. My 480w leds are only 30w/sqft but I hit a dli of 60 on 12/12 umol/w is the metric you want to look at some of these new lights are super efficient.

so your canopy is getting 1400 ppfd is that what you’re saying? 4x4 480w 1400 umol/s/m2 from wall to wall?

 

[Dank Bongula]

Autos?
With leds watt/sqft is generally a shitty metric. My 480w leds are only 30w/sqft but I hit a dli of 60 on 12/12 umol/w is the metric you want to look at some of these new lights are super efficient.

Yes, autos...I certainly prefer photos and have noticed a difference in response to nutes, light and temp with these last two runs of autos. Hopefully it was just a bad batch of beans from Mephisto...I could not turn my light up over 60% but with the photos I increased the light to max during stretch.

 

[Stunx]

Yes, autos...I certainly prefer photos and have noticed a difference in response to nutes, light and temp with these last two runs of autos. Hopefully it was just a bad batch of beans from Mephisto...I could not turn my light up over 60% but with the photos I increased the light to max during stretch.

What happened when you went over 60%? One of my autos spends most of it's time wilting in my tent, not all the time just more time than not and doesn't do it when I bring it outside. None the less, it's still growing very well.

 

[LeastExpectedGrower]

With leds watt/sqft is generally a shitty metric. My 480w leds are only 30w/sqft but I hit a dli of 60 on 12/12 umol/w is the metric you want to look at some of these new lights are super efficient.

I don't go that high, but I agree...My real concern is to hit reasonable DLI range at 12/12 evenly in the tent. I'm not necessarily interested in hitting 60DLI but closer to 45-50DLI max in flowering. Were I in a sealed environment with additional CO2 support, then I'd be looking at 50-60.

But I generally buy into this chart (and a few others that are similar)"

If you're growing autos, then you can remain in 18/6 and don't need the same firepower because you've got that additional 6 hours a day in flowering.

 

[Dank Bongula]

What happened when you went over 60%? One of my autos spends most of it's time wilting in my tent, not all the time just more time than not and doesn't do it when I bring it outside. None the less, it's still growing very well.

Wild heat/light stress. Light is atleast 24in away, I do not recall exactly. It is secured to the top cross member of my 6.5ft tall 3x3 tent. 80-83° lights on (exhaust kicks on at 83°), 73° lights off, cloudline t6 for exhaust, tower fan and turbo fan inside for circulation (nothing pointed directly at plant), 40-55%rh....during the day it is in the 40-50% range and at lights off the exhaust kicks on when it hits 55%. Earlier autos from mosca and short stuff didn't do this while also under similar but slightly cooler conditions.

 

[Lenin1917]

so your canopy is getting 1400 ppfd is that what you’re saying? 4x4 480w 1400 umol/s/m2 from wall to wall?

Pretty much, I’m running 2 in an 8x4 though. A mars hydro fce 4800 and a 480w samphon bar light

 

[crimsonecho]

Pretty much, I’m running 2 in an 8x4 though. A mars hydro fce 4800 and a 480w samphon bar light

are these your par readings or the manufacturers? because to be honest first of all 1400 is way to high for non co2 setups. secondly i’m doubtful that fce4800 can provide 1400umol in the corners and the edges of the tent.
and now that i checked the par map posted on the mars hydros site i see that these provide barely 1100umol in the middle and not doing particularly great on the edges and the sides. so i dont think you’re running 60dli in there more like 40-45 based on that 1000ish umols across the canopy. which is also fine 40dli is good.



and as i said 30w/ft2 is basically adequate light for growing. not too much not too little. now when the leds become even more efficient i’m gonna lower that baseline accordingly of course but for the time being, i’m telling all the newbies who dont know what dli or ppfd means or cant understand umol/j etc, shoot for 25w/ft2 min, 30 is just great without co2. this metric is based on the efficiency of the leds so its somewhat convertible imo.

 

[Lenin1917]

I just put my iphone under it at canopy level with the Photone app. I don’t run that high all the time though basically from the end of stretch in flower on.

 

[Lenin1917]

The samphon for sure is brighter than advertised, 300 - 400 par not a foot off the floor light literally at the top of the tent

 

[crimsonecho]

oh yeah i dont think mars would under-advertise their shit, nothing can make me believe that haha.

ok photone app has a bit of a deviation from an apogee meter and stuff as i remember. i dont remember it being higher than about 10% but it seems in your case i think its giving you an even higher reading than its supposed to give. those numbers up there are inside a tent so covered with reflective surfaces and the test is done by the manufacturer so you know they’ll do the best they can to get the most out of it and still only a couple of squares in the middle exceeds 1300 at 20cm.

i’m telling you you’re giving them 40-45 dli tops and thats a good thing because you’re not running co2 right?

 

[Dank Bongula]

I just typically use a par map as a baseline and watch the leaves' response. I am a home hobby grower, typically no more than 3 plants in each tent (2) at a time. Where is a good starting point/source in reading up and learning more about dli? Or is it even necessary for my situation?