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CMH vs LED vs HPS

Gerardbutler79

Well-known member
Veteran
I wanted to get input on the results you guys are getting with these in the finished product. I've had great results in the past with HPS supplemented with additional UVB from a zoologist mega ray bulb. I'm wondering if the CMH provides enough UVB on it's own if used in bloom?
 

snakedope

Active member
Ive also had great results always with HPS, didnt try UVB yet as under HPS my bud is too killer as it is haha, if you go the UVB route with additional lights, use LEDs, you can get any nm you want, in any array you want, its too simple to pass on, some learning is required to dial the nm in terms of which to use and how much and when but if you research for a few days things should clear up so you can start applying LED UV diodes next to your main light.

CMH bulbs do emit uv but not sufficient to say, yeah its the uv in cmh that does the difference..
Its good because its a mini sun, like LED, but with much more intensity.
Always use them in conjunction, CMH with LED UV, HPS with LED UV, or just CMH alone will grow very good quality as far as i seen.
 

Gerardbutler79

Well-known member
Veteran
Ive also had great results always with HPS, didnt try UVB yet as under HPS my bud is too killer as it is haha, if you go the UVB route with additional lights, use LEDs, you can get any nm you want, in any array you want, its too simple to pass on, some learning is required to dial the nm in terms of which to use and how much and when but if you research for a few days things should clear up so you can start applying LED UV diodes next to your main light.

CMH bulbs do emit uv but not sufficient to say, yeah its the uv in cmh that does the difference..
Its good because its a mini sun, like LED, but with much more intensity.
Always use them in conjunction, CMH with LED UV, HPS with LED UV, or just CMH alone will grow very good quality as far as i seen.
thanks for the reply snakedope. I’ve never heard of LED UV before I was under the impression LED’s don’t emit UV. I’ll have to research this
 

zachrockbadenof

Well-known member
Veteran
i've been growing the last few grows with '2' 315 cmh with phillip bulbs in a 4x3.5ft tent - prior to the cmh, grew with '4' 1000w hps/mh switchable's in a corner of a large room - the bud growing with cmh is 'ok', certainly not as good as hps/mh, and the penetration with cmh is not so good - i'd like to try led's , but fear the penetration will be worse the cmh's-
 

Hammerhead

Disabled Farmer
ICMag Donor
Veteran
I started indoor using HPS many many decades ago.. I then transitioned to CMH and got my best results.. I've stayed with CMH until late 2021. In late 2021 I started testing LED with mixed results. Some runs are OK some not so much. None so far are as good as CMH for me. I make a ton of seeds all the time, led has been a struggle to make Fem pollen. Using CMH lights to make Fem pollen work every time. Im still on the fence about using only LED. Im still trying to get them working as well as CMH does.. My flower room is a mix of CMH/LED. No plans to change to all LED.
 
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S

sallyforthDeleted member 75382

I’m happy with CMH and I still use HPS. I’ve spent lots on LED and it was a bad move in terms of quality plus I had to use Cal/mag shit that fucked in the quality. Flowers and plants looked great and yield was good. The photons from LED are too energetic. I have no problem using the LED’s I do have to supplement and increase light levels but I only use them on their own to veg and not flower.
 
Never switch to a full LED setup, you can supply some diodes with your HIDs, thats the ultimate way of getting into the field of UV supplements.

If you switch to a full LED array, you will lose 80-90% of your quality, even with UV present.
Really? 80-90 percent that seems like a lot so your saying -droplets that use led are growing pure garbage? I seen plenty of fire grown with leds
 

Mitsuharu

White Window
Veteran
When you would loose 80 - 90% quality with LED then people would not get high... So why are so many people are now growing with LED when it's so super bad like you are saying @skunkfunk !? 🤨

Seems like there is some kind of hate going on against LED from your side, why is that!? Is there a anti-led industry which you are lobbying for? :unsure:
 

snakedope

Active member
Really? 80-90 percent that seems like a lot so your saying -droplets that use led are growing pure garbage? I seen plenty of fire grown with leds
Well, define fire...
Could be your definition is different then mine, I haven't smoked fire with LEDs yet, and I smoked all jungle boyz lineup, cookies, you name it.. almost every strain that's new, top breeders and low ones... Im not saying LEDs won't give u good bud, in some instances maybe they would, my opinion is that with HIDs you will get better results, way better, you think not ? Your entitled to, won't hate ya for it ;)

When you would loose 80 - 90% quality with LED then people would not get high... So why are so many people are now growing with LED when it's so super bad like you are saying @skunkfunk !? 🤨
Saving money, that's the first reason
2nd reason is to create addictes, if you give killer Bud to people they will consume less and buy less.
Back in the day I used to smoke 20g a month of Purple Kush, any more then that and I'm officially a zombie... These days I smoke more then 50g a month cuz the quality is so bad.
Add 30g a month in money terms... More then double their profit.
3rd reason is lies and hype, we have knowledge of process and plants that goes back many years, knowledge that is backed by reality and nature, killer dank that people grew with poor spectrum lamps.
This "new" knowledge, like adding intensity by adding another same intensity source, false spectrum maps, low voltage bulbs/diodes
Is yes, lies.
You will grow healthy plants under LEDs, but in flower the story is different, you need other aspects of light, not qty of it in the space but a high intensity source to light stress the plant enough to produce it's defense mechanism to its fullest potential.
Seems like there is some kind of hate going on against LED from your side, why is that!? Is there a anti-led industry which you are lobbying for? :unsure:

Yeah it's called the truth industry have you heard about it ? We are losing a lot of money now because lies are everywhere driving our stock prices down !
 

tonykevin

Active member
I recently finished my first led grow and can say that compared to ndl the quality and quantity is clearly better.
Previously had 250w ndl and now a Sanlight Evo 4 250w. Buds are much denser, heavier, and more resinous. I also think the flavors are better.
The results with Ndl were never bad either. But i can already tell from the Light that the Sanlight is better. The Plants grow better. more quickly.
The Sanlight has Far Red.. no UV

I'm also surprised that Led should be so bad. So I don't have 80% worse quality. But calmag problems yes. And you have the feeling that the efficiency is almost too strong. The plants sprout slightly at first but agei get closer there are other problems.
The Light is quite strong but you haven't balanced the feeling quite perfectly. I don't know much about LEDs etc. I buy plug and play
 
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Gooseman23

Active member
Well, define fire...
Could be your definition is different then mine, I haven't smoked fire with LEDs yet, and I smoked all jungle boyz lineup, cookies, you name it.. almost every strain that's new, top breeders and low ones... Im not saying LEDs won't give u good bud, in some instances maybe they would, my opinion is that with HIDs you will get better results, way better, you think not ? Your entitled to, won't hate ya for it ;)


Saving money, that's the first reason
2nd reason is to create addictes, if you give killer Bud to people they will consume less and buy less.
Back in the day I used to smoke 20g a month of Purple Kush, any more then that and I'm officially a zombie... These days I smoke more then 50g a month cuz the quality is so bad.
Add 30g a month in money terms... More then double their profit.
3rd reason is lies and hype, we have knowledge of process and plants that goes back many years, knowledge that is backed by reality and nature, killer dank that people grew with poor spectrum lamps.
This "new" knowledge, like adding intensity by adding another same intensity source, false spectrum maps, low voltage bulbs/diodes
Is yes, lies.
You will grow healthy plants under LEDs, but in flower the story is different, you need other aspects of light, not qty of it in the space but a high intensity source to light stress the plant enough to produce it's defense mechanism to its fullest potential.


Yeah it's called the truth industry have you heard about it ? We are losing a lot of money now because lies are everywhere driving our stock prices down !
Dude you’re clearly hating on LED… do you know the vast array of LED lights?for example if you think LED doesn’t have good penetration then instead of using small diodes opt for COB Led which gives great penetration. Also their is a vast amount of spectrums to choose from. And a vast amount of quality from poor to high quality. Did you test every light out there? Also you claim that you consume 50g per month now compared to 30g a month back then well aren’t you growing your own??? And you’re NOT using LED? So sounds like you are growing not so good stuff with your hps… I saw another post where you claimed LED can’t produce dense buds and then somebody showed you dense buds produced by LED. Come on man stop bashing LED as a whole and just say the LED that you tried didn’t work so well so you don’t recommend that brand. Not to mention every comparison is actually not a true comparison. I’ve yet to see anybody replace any new full spectrum LED watt for watt with hps and receive less quantity or quality. You see for example most will use maybe a 350 watt led to replace a 600 watt hps and still get comparable results. But if you want to really compare superiority then replace a 600 watt hps with 600 watts of any top brand full spectrum LED and then see the results. I’m not bashing hps I know it grows great bud, but LED has come a long way and definitely produces great quality as well.
 
You have to take the Uv blockr off, that'll keep the uv rays in:
20230128_182754.jpg




Regarding leds.. If they could put 15 different chips on a board, then why don't they?

20230128_181340.jpg




Anything short of a 12 band led is gonna grow poop! Rainbow spectrum is the future of growing mark my words.
 

JKD

Well-known member
Veteran
‘PlatinumLED’ sell 12 & 14 band lights, if that’s what you’re after.

I think commercial growers will opt for efficiency and yield, and lighting manufacturers will direct their efforts to satisfying that demand.
 
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kro-magnon

Well-known member
Veteran
I'm on my first run with LED, the plants are only at the first week of flowering but I have to say I'm really impressed by the growth they had in the short period of time they spent under the new light. I will add a HPS (dimmed at 250w first) to help rise the temperature because I'm not sure the plants will perform well enough with only 20/21°c with the LED on.
How did you manage heat with LED only ? Did the plants perform well enough with moderate temps when light on ?
In my room the temps drop to 18°c in dark period during winter, with my previous set-up the plants didn't mind the fresh nights they had, during light period the temps were rising to 23/24°c with 600w HPS.
 

Gooseman23

Active member
I'm on my first run with LED, the plants are only at the first week of flowering but I have to say I'm really impressed by the growth they had in the short period of time they spent under the new light. I will add a HPS (dimmed at 250w first) to help rise the temperature because I'm not sure the plants will perform well enough with only 20/21°c with the LED on.
How did you manage heat with LED only ? Did the plants perform well enough with moderate temps when light on ?
In my room the temps drop to 18°c in dark period during winter, with my previous set-up the plants didn't mind the fresh nights they had, during light period the temps were rising to 23/24°c with 600w HPS.
What LED are you running
 

ratatouille

New member
I'm on my first run with LED, the plants are only at the first week of flowering but I have to say I'm really impressed by the growth they had in the short period of time they spent under the new light. I will add a HPS (dimmed at 250w first) to help rise the temperature because I'm not sure the plants will perform well enough with only 20/21°c with the LED on.
How did you manage heat with LED only ? Did the plants perform well enough with moderate temps when light on ?
In my room the temps drop to 18°c in dark period during winter, with my previous set-up the plants didn't mind the fresh nights they had, during light period the temps were rising to 23/24°c with 600w HPS.
high temperature is important under LED, i recommend around 28-30 °c when light on. You could suck warm air via tube from a heater/radiator
 

snakedope

Active member
The problem starts when people take commercial ideas and implement them at their own hobby, like JKD said, the people who make those lights listen to the commercial market needs, and will release products that earn them the most money, not giving u the best results.

Led will produce high quality flowers in pics, in real life i haven't smoked a good one, and I smoked over 100 from the top growers with top lights to low growers with aliexpress QBs
Gooseman23, the fact that u think COBs are any better just shows you are caught up in the hype and don't understand the concept and math/numbers behind this tech.
 
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