Lighting Height restriction is a bummer.... how to remedy??

[Growtogrow]

Welcome back to AFN

Well let me say you do have a little bit of a dilemma with your height restrictions. But it's easy LST / EST extreme stress training is what your going to need to do. I do it all the time everytime I grow. For height restrictions and stealth.
Since the beginning I've always pulled my plants down and over.
So that the plant gets Optimum light usage from where it grows from. I learned these techniques has a gorilla grower in the late 70s - 80s and early 90s where I had to hide my grow from the authorities . Pulling a plan over was a great way for stealth very hard to see the plant when it's pulled down and surrounded by other vegetation. I learned very quickly that this also increased my yields. By the second year that I had done this. I know do it all the time There's so many ways to LST/ EST hundreds of ways.
With your height restrictions with a 12 inch pot leaving you not much room height. You could take & make a smaller pot with only has six inch tall sides. Because of cannabis plant doesn't need a lot of deep space it just needs a lot of wide space for the roots. The roots will go off to the side. You could use the entire bottom of your grow tent as a low raised bed. With this in mind that would give you an extra 6 inch of height. With topping your plants or plant using a photoperiod plant would be great.
There's so much you can do with a photoperiod plant.
You have much time to work with them. But with your height restrictions and your floor restrictions I don't see you vegging over 4 to 6 weeks.
I would look into manifolding your plants as well as a possible solution to your height restrictions.
And I just got to tell you I'm not a big fan of LED lights. I have my reasons. I don't think they're that efficient myself. I use CMH lights they run just as cool as the LEDs and you get more bang for your buck. It's just a better light in my opinion. The 315 CMH light you could probably run two of them in that space and still not have any problem with heat. In the winter time. But one light would be very sufficient in a 4x4.
I hope this was helpful to you.
You might want to also look into micro grows those guys got a lot of innovative techniques for growing in small spaces.

Good luck and Happy growing
From Growtogrow

Hello AFN!

Let me start by saying that I love this forum. So many knowledgeable people on here that have a major passion for growing. I could not have done my previous grows without your help (I posted a couple threads back in the day).

So my new setup that I have been slaving over is finally ready to rumble. My major concern is height restrictions.. from floor to ceiling i have roughly 39 inches to play with (roughly 4x4 room). My ceiling is floor joists so I have the ability to place the light in between them to truly get that 39 inches. Given that the pot will more than likely be roughly 12 inches tall, I am l left with 27 inches. Then when you factor in the light being around 12 inches from canopy during flowering, I am left with 15 inches.

My question is.... is there any way around having the lights 12 inches away from the canopy without burning or stunting growth? To remedy this I was looking into dimmable led lights, and my thought was that when the plant starts impeeding on that 12 inches, I can dim the light on top and throw in some side lights? Unfortunately I have not had much time to research lighting in great detail so my knowledge is limited as well as I am having a hard time finding useful pages for similar situations. Does anybody have any advice on where to start, or if there are any alternatives?

All the input is greatly appreciated.

Are you DIY inclined? Bridgelux EB gen 3 light strips would be my choice. Connect a meanwell type a driver and you would be good to go. You have a 4x4 area with no height that needs a strong PPFD. With the gen 3 you'll need around 480 watts. I've ran my gen 2 strips 6 inches from the canopy.

A light strip build whether you make it or Alibaba does is going to be your best choice for low profile. Fluence and many of the other low pro makers are going to be $1200 plus to cover a 4x4. DIY can do better for less than half the price.

Quantum boards are a nice choice as well but the larger ones have hot spots with the concentration of diodes and lesser ppfd at the edges.

What's your budget?

View attachment 1158510

Hi and welcome back to AFN. You aren't likely to find a friendlier or more helpful place to get information on growing from.

First, I suggest that you choose a light that permits the least distance you can find from the plants - all the major players give you specs on this. I suggest staying away from any light that has lenses over the LEDs - you do not want the light focused in a more concentrated cone for your purposes, you want it spread as widely as possible. I would be looking at a dimmable quantum board setup if I were you, and of course it will need to fit between your joists.

After sorting the light, your choices basically boil down to what you want to do to limit plant height. My off the cuffs are:

1. Choose strains known to be short and LST them aggresively to spread them out.

2. Consider topping, but check to see whether others have made it work with the strain you have in mind.

3. Heresy here I suppose, but you could consider photoperiod plants which offer more control over plant size, and permit more aggressive high stress training.

4. Do an aggressive SCROG to keep a lid on things.

5. Finally, consider using small pots, particularly low ones. You can grow a lot of bud in multiple small plants.

In any case, you can make it work. Even if the odd bud gets toasted there will be others that don't. The only thing worse than having to grow in a small space is not having anywhere to grow at all.

 

[Death The Cultivator]

Welcome back to AFN

Well let me say you do have a little bit of a dilemma with your height restrictions. But it's easy LST / EST extreme stress training is what your going to need to do. I do it all the time everytime I grow. For height restrictions and stealth.
Since the beginning I've always pulled my plants down and over.
So that the plant gets Optimum light usage from where it grows from. I learned these techniques has a gorilla grower in the late 70s - 80s and early 90s where I had to hide my grow from the authorities . Pulling a plan over was a great way for stealth very hard to see the plant when it's pulled down and surrounded by other vegetation. I learned very quickly that this also increased my yields. By the second year that I had done this. I know do it all the time There's so many ways to LST/ EST hundreds of ways.
With your height restrictions with a 12 inch pot leaving you not much room height. You could take & make a smaller pot with only has six inch tall sides. Because of cannabis plant doesn't need a lot of deep space it just needs a lot of wide space for the roots. The roots will go off to the side. You could use the entire bottom of your grow tent as a low raised bed. With this in mind that would give you an extra 6 inch of height. With topping your plants or plant using a photoperiod plant would be great.
There's so much you can do with a photoperiod plant.
You have much time to work with them. But with your height restrictions and your floor restrictions I don't see you vegging over 4 to 6 weeks.
I would look into manifolding your plants as well as a possible solution to your height restrictions.
And I just got to tell you I'm not a big fan of LED lights. I have my reasons. I don't think they're that efficient myself. I use CMH lights they run just as cool as the LEDs and you get more bang for your buck. It's just a better light in my opinion. The 315 CMH light you could probably run two of them in that space and still not have any problem with heat. In the winter time. But one light would be very sufficient in a 4x4.
I hope this was helpful to you.
You might want to also look into micro grows those guys got a lot of innovative techniques for growing in small spaces.

Good luck and Happy growing
From GrowtogrowView attachment 1158654



View attachment 1158654

Top bin diodes are more efficient than any CMH and some require bulb replacements lol.

 

[OttoCBD]

Depending on what kind of light you have, you might be able to do away with the ratchet hangers which will give you a chunk more of vertical space. Also, if your light hangs from cables you might be able to use a zip tie and fasten the cables from the opposing sides together so that it hangs from one central point. Then you can just raise and lower it with a length of rope and secure it with a cleat. Kind of like this..

 

[Growtogrow]

Top bin diodes are more efficient than any CMH and some require bulb replacements lol.

Been there and done that.
Yes bulb replacement is a must. The bulbs last for about 5 years. That's not a bad replacement value considering the cost of startup is only about a third of what the start up of an LED is. The CMH is more efficient than the LEDs too. Good quality LEDs only last about that long too 5 years. That's why over 80% of the commercial Growers grow with CMH lights.
Yes
LEDs have come a long way. I'll give you that.
But...
A CMH represents the Sunlight by 90% for the majority of its life and then only drops down to 85% maybe 80% depending on the bulb maker.
So yeah you can laugh if you want but I guarantee this.. I got more money in the bank than you do on this one..in start up cost and watts saving over leds
But it all comes to matter of choice. And for me I prefer the CMH way more than LEDs. I've had both top quality and HPS 1000 / 600 watt too. I've grown organically, hydroponically, in raised bed, in the ground outside, inside, in bags, scrog net, sea of green, ebenflow, aeroponics, but not aquaponics. But you name it man I've done it. There's not much I haven't done when it comes to growing cannabis,..besides micro grows.. Hat's off to those guys just too tedious for me. But I've ran them all dude.
I'm just giving you my two cents worth cuz I probably been growing longer than you have. With 10, of thousands of plants to my credit. And all kinds of mistakes and experiences to help a fellow grower out.
But y'all can take it or leave it don't 2 sh@ts... just trying to help a brother or a sister out to grow top quality AAA weed in a small height-challenged space. With my experiences. Because my grow ceiling in my flower room is only 6 foot to the light bulb face. So I know where he or she is coming from in my grow room.
Ok
I'm out.
Good luck and
happy growing

from Growtogrow

 

[Death The Cultivator]

Been there and done that.
Yes bulb replacement is a must. The bulbs last for about 5 years. That's not a bad replacement value considering the cost of startup is only about a third of what the start up of an LED is. The CMH is more efficient than the LEDs too. Good quality LEDs only last about that long too 5 years. That's why over 80% of the commercial Growers grow with CMH lights.
Yes
LEDs have come a long way. I'll give you that.
But...
A CMH represents the Sunlight by 90% for the majority of its life and then only drops down to 85% maybe 80% depending on the bulb maker.
So yeah you can laugh if you want but I guarantee this.. I got more money in the bank than you do on this one..in start up cost and watts saving over leds
But it all comes to matter of choice. And for me I prefer the CMH way more than LEDs. I've had both top quality and HPS 1000 / 600 watt too. I've grown organically, hydroponically, in raised bed, in the ground outside, inside, in bags, scrog net, sea of green, ebenflow, aeroponics, but not aquaponics. But you name it man I've done it. There's not much I haven't done when it comes to growing cannabis,..besides micro grows.. Hat's off to those guys just too tedious for me. But I've ran them all dude.
I'm just giving you my two cents worth cuz I probably been growing longer than you have. With 10, of thousands of plants to my credit. And all kinds of mistakes and experiences to help a fellow grower out.
But y'all can take it or leave it don't 2 sh@ts... just trying to help a brother or a sister out to grow top quality AAA weed in a small height-challenged space. With my experiences. Because my grow ceiling in my flower room is only 6 foot to the light bulb face. So I know where he or she is coming from in my grow room.
Ok
I'm out.
Good luck and
happy growing

from Growtogrow

Not laughing at you but preference doesn't mean what I said isn't true. I've seen side by sides of high end cobs versus cmh to suggest a low profile LED solution, doesn't even reach 80f per strip, and will provide stronger edge to edge ppfd than a cmh. My array is less than 6" in height and the OP is asking for a low profile solution that can be dimmed.

I'm not talking blurples but Samsung, Osram, bridgelux cree top bin diodes. It isn't about imitating the sun but about providing a spectrum that can give a grower the morphology they want for their situation. He wants a low profile solution, 4000k would keep internodes tighter and help limit stretching, and LEDs can offer him a custom spectrum that can be added to over time.

There are many commercial growers switching to low profile LED solutions for vertical farming and less impact on cooling solutions with better ppfd. If you get a Fluence build you're getting more at $1500 with waterproofing and other features plus a warranty and no bulbs. Life span can be extended through dimming as well. Tunable spectrum lights are a thing lol.

It's cool you got preferences and a vast amount of experience. I'm glad you're willing to share what you know with a lesser experienced grower like myself. We all know something and I'm not claiming to know everything.

 

[Disburped]

Idk what CMH cost but I doubt it's cheaper than that cob I posted on previous page. To replace 2 50W COB cost around five dollar and last 50000h. 450W with heatsink, wall mount and lenses would cost max 200. It's a chinese streetlight for parks, greenhouse or somethin, real quality aluminium heatsink but the cob is real cheap. There are also cheaper ones than that. I don't care about a good light cause my heart is and will allways be for the outdoor. Indoor is a fun little lab experiment for me. So easy to upgrade lights later anyway, if it is nice to work with it's ok for me, passively cooled cobs plug n play for that price is nice, can't complain shit on my cheap chinese street light, but that is me!

 

[Growtogrow]

Hey guys I appreciate you guys very much I just want to let you know that if it wasn't for afn I wouldn't be where I'm at today either. Afn is a great motivator.

Okay I can see you guys real passionate about what you do that's great....I am too and that's what we want to be right we all want to be passionate about how we grow our weed how we grow our medicine how good it can be what's the best thing we can do for our plants right?
So with that being said I know the debate goes on about CMH lights and LED lights and now Cobb lights LOL... it's just funny that we all got different ideas about what lights best.
I grant you that LED lights are coming along and Cobb lights... you know I really don't know a lot about Cobb lights they've never been on any radar Spectrum from where I try to be at so I can't say much about them and I'm sorry about that friends.
But I did find some tidbits this morning after reading FTF post. And I just wanted to throw a couple tidbits out here for y'all that I found.
Sorry I'm not a very good person about being able to give you guys links to things. but I took some screenshots of some highlights of some articles and you can look these articles up for yourself on Google. And they're very relevant late last fall and this year 2020 LEDs vs CMH articles.
So This is why I use CMH lights because of all these other commercial gardeners and professional Growers and what they tell me that they use for lighting and y.
And I'll tell you first off that when better technology comes out there that I can afford that makes sense also like economically make sense efficiently makes sense and Longevity makes sense. I'll buy it guarantee it.
So these are some highlights that I shot for you both. And this is my reasoning 100% for why I choose the CMH light over any other light that I've ever used and I have had some high-end LEDs and I got a friend of mine that run really high end LEDs they will cover my entire room one light he paid $1800 for it sure it looks great and works awesome but he's got the same dilemmas as what you got and he's eventually going to have to deal with it but he works at a grow store so he gets deals and can afford to buy new technology every time he turn around. LoL

Not laughing at you but preference doesn't mean what I said isn't true. I've seen side by sides of high end cobs versus cmh to suggest a low profile LED solution, doesn't even reach 80f per strip, and will provide stronger edge to edge ppfd than a cmh. My array is less than 6" in height and the OP is asking for a low profile solution that can be dimmed.

I'm not talking blurples but Samsung, Osram, bridgelux cree top bin diodes. It isn't about imitating the sun but about providing a spectrum that can give a grower the morphology they want for their situation. He wants a low profile solution, 4000k would keep internodes tighter and help limit stretching, and LEDs can offer him a custom spectrum that can be added to over time.

There are many commercial growers switching to low profile LED solutions for vertical farming and less impact on cooling solutions with better ppfd. If you get a Fluence build you're getting more at $1500 with waterproofing and other features plus a warranty and no bulbs. Life span can be extended through dimming as well. Tunable spectrum lights are a thing lol.

It's cool you got preferences and a vast amount of experience. I'm glad you're willing to share what you know with a lesser experienced grower like myself. We all know something and I'm not claiming to know everything.

Idk what CMH cost but I doubt it's cheaper than that cob I posted on previous page. To replace 2 50W COB cost around five dollar and last 50000h. 450W with heatsink, wall mount and lenses would cost max 200. It's a chinese streetlight for parks, greenhouse or somethin, real quality aluminium heatsink but the cob is real cheap. There are also cheaper ones than that. I don't care about a good light cause my heart is and will allways be for the outdoor. Indoor is a fun little lab experiment for me. So easy to upgrade lights later anyway, if it is nice to work with it's ok for me, passively cooled cobs plug n play for that price is nice, can't complain shit on my cheap chinese street light, but that is me!

So I guess that's what I'm trying to say guys you know. I'm just trying to help y'all and anybody else out there wants to read this because I've experienced a lot when it comes to Growing just in the last 7 years since I've actually been able to legally grow I've learned so much more about what I do and what it cost me to do it and what the best tools are for me to use to make it all happen... and I'm all about AAA bud. AND I will sacrifice everything off the bottom of a plant from the ground up to the first beautiful buds to get the AAA quality Bud from the top of that plant.
So research everything you do research it hard know everything about what you do. There's a lot of wacks and hacks out there.
I'm not one of them I'm out here to help you guys.
So I'm off to paint my grow room bright white with mold killing paint. I'm getting ready for the 2020 grow season inside now and outside on 420.

I'm out
Good luck guys happy growing.
I hope this helps you all

from Growtogrow

 

[Death The Cultivator]

Hey guys I appreciate you guys very much I just want to let you know that if it wasn't for afn I wouldn't be where I'm at today either. Afn is a great motivator.

Okay I can see you guys real passionate about what you do that's great....I am too and that's what we want to be right we all want to be passionate about how we grow our weed how we grow our medicine how good it can be what's the best thing we can do for our plants right?
So with that being said I know the debate goes on about CMH lights and LED lights and now Cobb lights LOL... it's just funny that we all got different ideas about what lights best.
I grant you that LED lights are coming along and Cobb lights... you know I really don't know a lot about Cobb lights they've never been on any radar Spectrum from where I try to be at so I can't say much about them and I'm sorry about that friends.
But I did find some tidbits this morning after reading FTF post. And I just wanted to throw a couple tidbits out here for y'all that I found.
Sorry I'm not a very good person about being able to give you guys links to things. but I took some screenshots of some highlights of some articles and you can look these articles up for yourself on Google. And they're very relevant late last fall and this year 2020 LEDs vs CMH articles.
So This is why I use CMH lights because of all these other commercial gardeners and professional Growers and what they tell me that they use for lighting and y.
And I'll tell you first off that when better technology comes out there that I can afford that makes sense also like economically make sense efficiently makes sense and Longevity makes sense. I'll buy it guarantee it.
So these are some highlights that I shot for you both. And this is my reasoning 100% for why I choose the CMH light over any other light that I've ever used and I have had some high-end LEDs and I got a friend of mine that run really high end LEDs they will cover my entire room one light he paid $1800 for it sure it looks great and works awesome but he's got the same dilemmas as what you got and he's eventually going to have to deal with it but he works at a grow store so he gets deals and can afford to buy new technology every time he turn around. LoLView attachment 1159057View attachment 1159058View attachment 1159059View attachment 1159060View attachment 1159061View attachment 1159062View attachment 1159063View attachment 1159064View attachment 1159065View attachment 1159066View attachment 1159067



So I guess that's what I'm trying to say guys you know. I'm just trying to help y'all and anybody else out there wants to read this because I've experienced a lot when it comes to Growing just in the last 7 years since I've actually been able to legally grow I've learned so much more about what I do and what it cost me to do it and what the best tools are for me to use to make it all happen... and I'm all about AAA bud. AND I will sacrifice everything off the bottom of a plant from the ground up to the first beautiful buds to get the AAA quality Bud from the top of that plant.
So research everything you do research it hard know everything about what you do. There's a lot of wacks and hacks out there.
I'm not one of them I'm out here to help you guys.
So I'm off to paint my grow room bright white with mold killing paint. I'm getting ready for the 2020 grow season inside now and outside on 420.

I'm out
Good luck guys happy growing.
I hope this helps you all

from Growtogrow

All that doesn't apply to full spectrum diodes like Samsung's or Optisolis at all. CMH compared to blurples is a completely different topic.

LED manufacturers offer 80 and 90 cri that can be tuned from 2700k - 5700k through drivers or even a phone.

The quote isn't from me but stems from 2017 and is quite accurate. It doesn't account for quantum boards or any of the newer diodes between 2017 and now. The Fluence light is the best one and the most expensive because it's for c02 growing.

What the par is PPFD?

PAR just means Photosynthetically Active Radiation; it's not a measurement, just defining the range 400-700nm. 400-700nm is used by plants for photosynthetic growth and is a more specific range of the light spectrum for horticulture than lumens which is the range of light visible to the human eye. PPF is the total amount of PAR photons a panel emits and is measured by the manufacturer in one of those fancy spheres. But PPF is not exactly reflective of how many photons are hitting your canopy. Handheld PAR meters are measuring PPFD, which is the amount of par photons hitting a square meter per second.

(not my graph)

This study, published in 2009, established that cannabis sativa grows best at 30 degrees celsius and will grow quicker from increased PPFD, capping off in the 1500's. There's a diminishing return however. At 300 PPFD, cannabis grows at about 45% speed. Increase that to 800 PPFD, and cannabis grows at about 85% speed. That 40% gain for 500 extra PPFD is easily achievable. But to max out at 100%, you would need to go all the way to 1500 PPFD, nearly doubling the light intensity for a small 15% gain over 800 PPFD.

The best flowers will no doubt be grown at the highest PPFD, regardless of efficiency. It's up to you to make the decision between what's important to you between cost, efficiency, and quality. These graphs will hopefully help others decide which light is best for their space and what heights they need to be at for clones, seeds, veg, flowering cannabis.

Optimal PPFD for Cannabis Stages:

(table by Fluence Bioengineering)

My testing was done in a 4x4 grow tent, taking measurements on the floor with a handheld hydrofarm PAR meter. The 4x4' testing plane was divided into 6" squares and PPFD values were measured at the center of each square. The meter sometimes swings up to 100 PPFD in either direction, particularly for the Mars panels. I just took the average in this case, but I think it was because the blue and red spectrums are different intensities and it was confusing the meter. The SE450, Spydrx Plus, and CMH were much more stable on the PAR meter, maybe because of the "full-spectrum" of white light.

Factors that may tamper with the accuracy of my data or your own results would be the quality of the par meter, positioning of the light source, age of the light, the reflectivity of the tent, the tent door being open or any other light leaks while taking data. There's a huge difference in PPFD directly below the panel, compared to just inches outside of the direct footprint. The difference on the edge of the footprint could be more than 500 PPFD across a couple inches. Even though I took data every 6", if that footprint edge fell in or outside of my data points, that could make a big difference in the graphs. But the vast quantity of data points every 6" at multiple heights should dampen those factors in the averages. The panel dimensions are included in the graphs so you can see how dramatically the PPFD drops outside of the actual footprint. Look into the Inverse Square Law to read more about why this is important.

My first light was the MarsII 1200. It is marketed for a 4x4 foot grow. I used it in a 3x3' though and I'll show you why you should too. Sadly, the MarsII 1200 is probably only good for a 2x2' space if you really wanted to push for the perfect flowers with CO2 supplementation and everything else maxed out. It will no doubt grow cannabis in a 4x4' space, but the outside 1' ring of that tent is going to be getting only 150 PPFD which is only 25% of maximum growth rate. This sparked my quest to buy a meter and different lights to answer the question: Which light can

Let's get right into it. Here are the graphs of PPFD data that I've made for the lights I have. All of them are marketed for a 4x4' space by their manufacturers.

.

Pretty, right? Next post will be averages and looking at the data.

For the 2x2 averages i took the center 16 squares of the 4x4 graphs and averaged them, then the center 36 squares for the 3x3 averages. 4x4 averages are of all 64 data points per height.

At this point it should be kind of obvious from the graphs that there's only one light here that's actually powerful enough or designed properly for a 4x4' space. The SpydrX Plus is by far the top performer in a few ways. I don't think I need to make more graphs to explain why but here's a few more calculations:

Efficiency

Wattage:
Reflector 192: 387w
MarsII 1200: 490w
Philips CMH: 315w
Amare SE450: 450w
SpydrX Plus: 660w

Optimal height PPFD per Watt:
XPlus @ 6": 1.66 in 2x2, 1.62 in 3x3, 1.54 in 4x4
CMH @ 12": 2.72 in 2x2, 1.63 in 3x3, 1.07 in 4x4
192 Bloom @ 12": 2.42 in 2x2, 1.4 in 3x3, 0.86 in 4x4
1200 @ 18": 1.28 in 2x2, 0.81 in 3x3, 0.54 in 4x4
450 @ 18": 1.98 in 2x2, 1.25 in 3x3, 0.82 in 4x4
450 Lens @ 24": 2.58 in 2x2, 1.48 in 3x3, 0.88 in 4x4

Penetration

PPFD Loss per 6" in 2x2:
xPlus: 15%, 13%, 12%, 8%, 8%
CMH: 35%, 27%, 22%, 18%
192 Bloom: 22%, 26%, 21%, 21%
Mars 1200: 25%, 23%, 20%
450: 23%, 20%, 16%
450L: 14%, 15%, 13%

Average PPFD Loss per 6" in 2x2:
XPlus: 11%
CMH: 26%
Reflector 192 Bloom: 23%
Mars 1200: 23%
SE450: 20%
SE450 Lens: 14%

Price:
SpydrX Plus: $1500
CMH: $225 ($75 bulb + $150 reflector)
Amare SE450: $1200
MarsII 1200: $350
Mars Reflector192: $275

Ok now we can talk about the data. Because of the inverse square, all of the lights that were from a single center source performed poorly in the 4x4' grid. The Spydrx Plus beat this by having a massive 42" square size. The SpydrX Plus would still have the same issues of dramatically poorer performance in a 5x5' or 6x6' space, but its size happens to match perfectly to a 4x4' tent.

The other LEDs and CMH were way too intense at close heights. They have to be 12-18" high to not only spread 4 feet wide, but to simply not burn your plants. This is wasted energy because you're basically lighting 12" of vertical space for no yield. The most efficient light will be dropped directly on top of the canopy to get maximum PPFD for your power usage. SpydrX Plus wins here again by having LED's spaced wide enough that it's not too intense to bring the light within 6" of a flowering canopy.

But what about penetration? I've read that LED grows should shoot for about 18" of vertical canopy flowers. If you have to have your light 18" above the canopy already, and then account for 18" of high-par flowers, you better hope your light is still strong at 36". The Amare SE450 with lenses should have won here I think because the lenses create a spot light effect with the super powerful COB chips. But again, the coverage of the SpydrX Plus appears to be working with the reflective walls of the tent to maintain a high PPFD reading even at 36" away. Keep in mind the wattage though, the X Plus is just way more powerful than the other lights by default.

The Spydr X Plus is also the most expensive. Five times more than the Reflector 192. You should consider that the best light setup in a 4x4 may not actually be the SpydrX Plus if you can't afford it. Two CMH's in a 4x4 would probably be devastatingly good, or two reflector 192's. The CMH gets a special mention for having the most efficient PPFD per Watt in a 2x2 space, although it also had the worst penetration efficiency.

At the end of the day there's a lot more to consider besides PPFD when making a purchase and designing your grow. You should consider the spectrum, warranty, lifespan, cost, wattage, efficiency, shape, etc. But hopefully this data gives you some goals and ideas. Thanks for reading!

 

[Growtogrow]

Well that information was okay buddy. Thanks.
But at the end of the day the article did say the CMH was a better light even if it's old information or not.
Surely Way less expensive than that led by Leaps and Bounds right. I mean for the cost of that one LED at $1,500 I could turn my entire basement into a grow room with the 315 CMH with Philip bulbs.
Now the cost of his CMH was a lot higher than what I'm paying for that stuff. Like the reflector I only pay 30 bucks. the bulb is 90 for a good Philips bulb and the CMH from Hydrofarm that I use cuz it comes with a conversion kit is 130 bucks. So I've convert all of my reflectors with that.
No I don't use any cooling system in mine I have no need to. My grow room is actually kind of chilly and I have to heat it actually even with the wing reflectors or parabolic reflectors and open bulbs.
But the articles pretty much concluded that CMH lights a better light in the long run still. But I appreciate all that information that's great stuff and anybody who reads this can make informed decisions from that thanks for your input though I appreciate that very much and so does afn...
I'll tell you what the UV protection is really a must that's another reason why I like this CMH lights they got a lot more UV. Cuz my neighbor has a lot of mildew in her yard and it got in my house and in my grow room that's why I'm redoing my entire basement. I'm repainting the whole thing with moldicide killing paint. I'm eliminating that problem. Best I can. I will add some reptile lights with the high UV concentration to help defend against mildew and mold.
To further my strategy against this nemesis.

 

[Death The Cultivator]

Well that information was okay buddy. Thanks.
But at the end of the day the article did say the CMH was a better light even if it's old information or not.
Surely Way less expensive than that led by Leaps and Bounds right. I mean for the cost of that one LED at $1,500 I could turn my entire basement into a grow room with the 315 CMH with Philip bulbs.
Now the cost of his CMH was a lot higher than what I'm paying for that stuff. Like the reflector I only pay 30 bucks. the bulb is 90 for a good Philips bulb and the CMH from Hydrofarm that I use cuz it comes with a conversion kit is 130 bucks. So I've convert all of my reflectors with that.
No I don't use any cooling system in mine I have no need to. My grow room is actually kind of chilly and I have to heat it actually even with the wing reflectors or parabolic reflectors and open bulbs.
But the articles pretty much concluded that CMH lights a better light in the long run still. But I appreciate all that information that's great stuff and anybody who reads this can make informed decisions from that thanks for your input though I appreciate that very much and so does afn...
I'll tell you what the UV protection is really a must that's another reason why I like this CMH lights they got a lot more UV. Cuz my neighbor has a lot of mildew in her yard and it got in my house and in my grow room that's why I'm redoing my entire basement. I'm repainting the whole thing with moldicide killing paint. I'm eliminating that problem. Best I can. I will add some reptile lights with the high UV concentration to help defend against mildew and mold.
To further my strategy against this nemesis.

Yes, the CMH is better price wise compared to a commercial LED fixture intended for c02 injection that is waterproofed. Plus the CMH had the worst penetration.

The ppfd is great for the cmh that is in a 2x2 at 30" but that doesn't help the OP lol. 30" for 800+ ppfd and you would still need two for a 4x4 however the edge ppfd is going to be bad still. The Fluence can be ran at 12 inches and have an average 900 ppfd all the way around.

I'm not saying anyone shouldn't grow with A CMH but compared to modern top bin diodes it is still inferior especially where low profile solutions are needed.

https://m.alibaba.com/product/62257411405/detail.html?spm=a2706.wapshop.0.0

Or even

Meijiu A8 650w Samsung Lm301h Horticulture Red Led Grow Light Waterproof Etl Dlc Lm301b Grow Lights 1000w 1200w - Buy Samsung Lm301h,Lm301b Grow Lights 1000w 1200w,650w Grow Light Product on Alibaba.com

Meijiu A8 650w Samsung Lm301h Horticulture Red Led Grow Light Waterproof Etl Dlc Lm301b Grow Lights 1000w 1200w - Buy Samsung Lm301h,Lm301b Grow Lights 1000w 1200w,650w Grow Light Product on Alibaba.com

m.alibaba.com

Watts can be had on the cheap with LEDs through DIY or Alibaba. Both of those lights have a 800+ average par all around a 4x4 around 12". You would need 2-4 315s in a 4x4 around 12" to match the aboce lights or get close but then the BTUs of the CMH are going to reduce the efficiency.

Technically commercial cultivators are using CMH predominantly because they are dirt cheap and work lol.

Like I said, I respect your preferences and I'm glad this has remained civil but modern top bin diodes trump CMH in performance and efficiency especially in strip configurations. At one point it was incredibly costly to get into blurples then it was expensive to get into cobs, and it's getting less expensive for pcb mounted diodes that offer full spectrum and high umols.