2 a light

I don't visit the LED section as much. Just wondering how people have advanced since +50% efficiency has become common.

So how much wattage does it take to get 2 for you? If you have a small grow you can extrapolate. For instance, 4 zips from a 100w light = 800w for "2 a light". Math: 32 / (your zips) * (your wattage) = X for 2 a light.

Great question. We are hitting 2.0-2.5+ per 4x4 with 3 year old CD bin cree cobs dimmed way down to roughly 21-25 watts per chip. In this video the 2 outside lamps are at 400 and the middle one is at 350. Got the lamps as close as we can go, out of ceiling height too lol, vegged em a bit too long but still working out great.

Strain is black indica
10 plants
10 week veg
5 gallon fabric pot
1650 co2
1280 veg ppm
1280-1650 flower ppm
plants are at 8 weeks and 2 days since flipping to 12/12
I also check run off on almost every feeding.


Youtube video of the plants with par reading, leaf temp reading, watt reading etc.:
There is 575 watts per 4x4 here, we expect to get similar results with 450-500 watts with the new lm561c and lm301b powered bcblondes rigs when they come in.

Id love to see other peoples low watt 4x4 or 5x5 pics/videos!

pirg420 said:

Great question. We are hitting 2.0-2.5+ per 4x4 with 3 year old CD bin cree cobs dimmed way down to roughly 21-25 watts per chip. In this video the 2 outside lamps are at 400 and the middle one is at 350. Got the lamps as close as we can go, out of ceiling height too lol, vegged em a bit too long but still working out great.

Strain is black indica
10 plants
10 week veg
5 gallon fabric pot
1650 co2
1280 veg ppm
1280-1650 flower ppm
plants are at 8 weeks and 2 days since flipping to 12/12
I also check run off on almost every feeding.


Youtube video of the plants with par reading, leaf temp reading, watt reading etc.:

There is 575 watts per 4x4 here, we expect to get similar results with 450-500 watts with the new lm561c and lm301b powered bcblondes rigs when they come in.

Id love to see other peoples low watt 4x4 or 5x5 pics/videos!

Click to expand...

Sounds like you're right on the doorstep of the magical "2g/w" grow. That's fucking killer, man.

Rahz said:

I don't visit the LED section as much. Just wondering how people have advanced since +50% efficiency has become common.

So how much wattage does it take to get 2 for you? If you have a small grow you can extrapolate. For instance, 4 zips from a 100w light = 800w for "2 a light". Math: 32 / (your zips) * (your wattage) = X for 2 a light.

Click to expand...

You're not taking into account that a small tent/closet grow is way easier to hit decent #s than a 10k+ one....... growers with experience on both ends will agree with my opinion?

PSUAGRO. said:

You're not taking into account that a small tent/closet grow is way easier to hit decent #s than a 10k+ one....... growers with experience on both ends will agree with my opinion?

Click to expand...

I would agree. But sometimes tent guys dont have ac or c02 though too....

Per light isnt the same as GPW ... per light puts a limit on the square feet used....

PSUAGRO. said:

You're not taking into account that a small tent/closet grow is way easier to hit decent #s than a 10k+ one....... growers with experience on both ends will agree with my opinion?

Click to expand...

Can you give an example of why a tent is easier to hit numbers?

pirg420 said:

Per light isnt the same as GPW ... per light puts a limit on the square feet used....

Click to expand...

2 per light comes out to 1.16 gpw not including ballast. I'm just asking how many watts it takes to hit 2 with people's current LED setups. There's a claim about 600w replacing a 1000w bulb that's been around for years, and while back 4 maybe 5 years ago it was possible to do that DIY, not many did due to the cost associated at the time. Now that +50% efficient setups are more common I'm just curious what wattage it's taking to beat a 1000w SE. What percentage of people are getting 2 using a 600w output or less setup?

Most setups aren't going to be exactly 600w, but the formula I provided should give a good idea of the general efficiency of their setup in comparison to a 1000w bulb. 2 per light surely isn't the best a 1000w bulb can do, but it's a common benchmark and would be considered good to hit those numbers.

Rahz said:

Can you give an example of why a tent is easier to hit numbers?



2 per light comes out to 1.16 gpw not including ballast. I'm just asking how many watts it takes to hit 2 with people's current LED setups. There's a claim about 600w replacing a 1000w bulb that's been around for years, and while back 4 maybe 5 years ago it was possible to do that DIY, not many did due to the cost associated at the time. Now that +50% efficient setups are more common I'm just curious what wattage it's taking to beat a 1000w SE. What percentage of people are getting 2 using a 600w output or less setup?

Most setups aren't going to be exactly 600w, but the formula I provided should give a good idea of the general efficiency of their setup in comparison to a 1000w bulb. 2 per light surely isn't the best a 1000w bulb can do, but it's a common benchmark and would be considered good to hit those numbers.

Click to expand...

I gotta admit, if you put one of these newer high end leds on a 5x5, pulling 2 per should be pretty easy. Even with out c02.

What about g/sq ft?

OneHitDone said:

What about g/sq ft?

Click to expand...

It's a good metric. People should feel free to include it but not really what I'm after.

Citi 1825 @50w each, total wattage: 400w and 24zips: 32/24=1.33 so 400*1.33= 532
Vero 18g7 @30.5w each, total wattage: 701.5 and 28zips: 32/28=1.14 so 701.5*1.14= 800 (I think can do better with this setup)

The Veros are running at 44% efficiency. The Citi chips are running in the near 60% range and 532w for 2 units represents best effort so far.

These days the best way to show off your yield and efficiency is to state the growing area size as well as the watts used and the veg time.

GPW can be misleading as a guy could have high GPW but still have small buds cause he used a low intensity led light that is massively spread out.

Pounds per light can be misleading as well, as comparing a 1220 watt gavita(1150 setting) on a 5x5 vs a regular 1000 watt hps on a 4x4 isnt fair.

who else has low watt led with minimal clearance on a 5x5 or 4x4? I have an 1100 watt rig on a 5x5, but the plants are too tall and i have to keep the light dimmed to about 560 watts in order to not destroy them, it hasnt been ideal but still not bad, ill post a vid a little later, it will probably slay on GPW but only OK on Pounds per light....

Think about how batshit crazy hps guys would be if i told them im pulling 4-5 off 1150 watts.... with out stating its on a 4x8 lol..

It will always depend how hard you run your light as it will directly affect efficiency lm/w.. for a 1000w SE id say about 600w ran at good power but you can probably achieve the same with 500 or 550w if you use more diodes and less current which boost effiency.. to get 2 pound id say 700-750w but once again depend if you use co2(probably a good +20% yield),which strain you use how hard you run your light, grower experience.. etc there is so many factors to consider.. hitting 2g/w would require only 450w of efficient light.. but upfront cost come into play for many of us

Heres my 5x5 with 12 plants. They are way too tall and had to dim the BCB 1100 way down. Even at 565 watts hitting huge par numbers at the top of the colas.

5x5
12 plants
10 week veg
1650 co2
1280-1650 fertilizer ppm
aggressive defoliation
feed every 2 days
fabric pots


Not necessarily the best run, total yield will be less than normal but this will show great GPW. its not really ideal, but trying to make due.

expecting 2.0-2.5 pounds and 1.6-2.0 gpw.