Thank you!
2 Likes
You can get an LED rig any size you want. But there are also small HPS.
Lots of reasons to use an HPS. They work.
As has previously been mentioned. LEDs are more expensive up front, but you donāt have to spend any extra after the fact.
But more important is that your electric bill will thank you. My HLG LED covers a 2x2 and only costs 12 cents a day to run. I did the math.
Shit I even switched to LED for the rest of my house. They used to run heavy watts but for $80 I got LED bulbs and now they run nothing. Everybody should do that.
I totally offset my growās power usage by switching out my kitchenās lights which was 480 watts. Itās down to 30.
Also with LED I donāt have to worry about a bulb exploding when Iām not there.
In short, LEDs are better thatās what I use and I like them.
9 Likes
Iām trying to figure out when to use LEDs and when to use HID
1 Like
It really depends on your growing style, your environment, and your preference of bud.
Some say thereās no right answer, I say there IS a perfect answer to every different situation.
HPS will provide a lot of heat, which causes plants to grow faster and you can grow fatter buds with it, and you will need more head room because the distance from the strong point light source needs to be larger from the buds, but conversely you also get a much deeper usable canopy depth, with fatter buds deeper down in the canopy than you would with LED. But with HPS itās not going to take much before you will have to start dissipating heat to outside of the grow area, which CAN be VERY good if you can use it as a form of heating when you are growing in a cold area.
BUT. If you have more of an insulated grow area or are growing in an otherwise already heated space, then you would be more inclined to grow with either CMH fixtures, or with LED type lights. The main difference between the two would be the type of bud you get and the grow style. With CMH you still get a lot of red in the spectrum which will contribute to fatter nugs like you would get with HPS, but it generates a lot less heat so you wonāt have to extract as much heat from the growspace, making ventilation a breeze (pun intended). You would still heave comparable head space to a HPS light. The price for CMH is between LED and HPS. A new bulb costs around 100 bucks, an entire system costs about 300 bucks, for the 315W fixtures that is (there are 630 ones as well). The 315 bulbs will give you the same output in grams than 500W HPS would give you.
With LED there is a difference between different led styles, but if you allow me to focus on what Iād call a current industry standard (I know thatās a bit of a blanket or bullshit statement but for ease of discussion, letās roll with it) of the samsung QBs made by HLG, this would translate into getting about 300 grams out from under a 260W quantum board, RENDERING LED THE LESSER OPTION. Pulling 300 or more from under a 260W QB V2 Rspec (my current max recorded under this setting was 370g, but out of that about 150g was larf, and that was with excessive training in a SCROGā¦) is definitely possible, but it will also take you a few weeks more, in those weeks POWER WILL STILL BE BILLED.
I have been running an HLG 100 for veg and an HLG 288 V2 for years now, added in red leds when they came out with the Rspec, and I run an additional UVR8 bulb, and let me tell you, LED is NOT where itās at, at least not for the bloom room. Thereās just too much fluff and too much time needed to get to harvest.
I donāt understand why people donāt see that. Itās a gram per watt story, and you have to count in how long it takes you to reach that number. And when all those numbers combine, there is only 1 winner for each situation.
Doing a low height grow with a lot of smaller containers filled with cuttings, thatās a LED board game, in my opinion.
If you want to grow bag appeal bud with potency and at an economic speed and cost in the average housing situation, go for CMH.
If you are about to spend on LED because of less heat.
Forget about it.
LED and CMH, watt per watt, generate the same amount of heat, or just about. Itās simply more dissipated over the board in the LED situation, but that wonāt matter jack shit. End of the line, the CMH will run you to harvest 2 weeks faster and the buds will be bigger for less of a hassle in plant training.
With heat you have to look at 2 things, the amount of heat you will generate in the leaves, thatās red spectrum heat, and the amount the source will produce thatās not in the form of light energy. With CMH, youāre basically looking at ideal ratioās of those types of heat, for the average indoor home grower growing inside an already relatively warm home.
But hey, thatās just me. Talk to someone who knows shit.
4 Likes
A light wave is a light wave ā¦ it goes same distance regardless of originā¦ initial led quality was much lower than new ones and some folks misinterpreted the dataā¦ it is easy to do it is a complicated subject with alot of variablesā¦
If a light wave is a light wave, and at the same time there are a shitload of variables, then I guess any light wave wonāt be the same as any other though, right?
From my pov, the biggest difference is the more customizable light spectrums.
Yield for me as a concern comes after quality.
Quality for me is tons of frost! Heheā¦
With hid you need to supplement ir and uvb for higher resin production, many leds incude this now.
Anectotodal story, i had 600w hps hooked up with lizard uvb lights jammed in a 3x3 at one point! Haha ā¦
Initial leds were kinda weak and could not match yield of hid. Tech advancements have largely changed that.
Between spectrum and magnification lenses leds match hid output now with less power n heat.
There are many sweet leds in the $500-600 range that will outshine hid in yield, spectrum, and cost of ownership long term.
I just picked up a higher end one the growers choice e 720 and it rocks!
2 Likes
The wave remains the same the variables changeā¦
Ah, thereās the more nuanced answer I like 
Iād like to contest that idea that any sweet led in the 500-600 range will outshine HID in terms of yield and spectrum. At least CMH. But thatās the thing. Who do you know who grows with CMH? Itās a lost segment.
Everyone who grows with CMH is quite impressed. No one Iāve spoken to who grows with CMH has been more impressed by a LED setup, and I know some have tried, with HLG boards IIRC, which I run too. Not a bad LED board by any standard AFAIK, and I do run additional UV bulbs and red leds as well, and still. Iām not that impressed.
LED has a very hyped momentum. People like to jump on the bandwagon.
About the heat, you ought to look up the difference in heat generation watt for watt between CMH and LED. Itās not much.
1 Like
People have gotten away from growing with cmh cause it is lower yield and high power out put. Even tho terp n thc are bomb!
Leds offer another oppurtunity, customizable light spectrums without that high power issue. Since, light travels same distance regardless of origin.
We are all space dust.
Growers choice e 720 has cmh color spectrum in led light format. I can change to others also like 1000w hps with controller.
2 Likes
I think you mean MH
CMH sees yields of 500G (17.5oz) or more under a 315W. EDIT: make that 450g tops.
How much heat does a 600W LED produce?
2,046 BTUs
A single watt of power is equal to 3.41 BTUs so a 600W luminaire will produce 2,046 BTUs. This is true for both the LED and the HPS luminaires.
So in comparison, one 600w HPS grow light puts off 2,400 BTU 's whereas one 315 W CMH grow light puts off only 1,260 BTUās , which is almost less than half the HPS light.
Off course the wattage is also about half
So, like I said, itās not much difference.
Itās the dissipation of heat creating the illusion of a cooler light.
Edit: Looking around for harvest weights online, I do gotta say I overestimated that number. It seems like 450g is a more accurate top weight, instead of 500 or more
[tries to get foot up in piehole]
btw who you calling spacedust, I wanna be a snowflake!
man how come we donāt have any weed smileys? I wanna have an emoji thatās vaping off a tabletop so I can illustratre my activities XD
Back to the growlights.
Iām going to go for CMH next time I buy a light. The LEDs will still have their place in my stable though, I might just be constructing another room to stick the ladies in for their final weeks, so I can run perpetual and give them a reduce in flowering hours at the end at the same time.
1 Like
Ive tried both and went with HIDā¦ I could never nail down LEDs. My basement is mid low 60s and everytime I try Led the healthy plants look unhappy and end up with deficiencies after a couple days. HID just works - they look happy, grow easily, and dont end up with deficiencies and me chasing it with sprays teas etc. Just my experience, lots have great success with LED, but for my KISS organic growing style, they really were not working for me. I really like my CMH light - awesome for veg and flower. Happy plants.
2 Likes
Did you ever try the 315w Philips Elite Agro CMH for bloom? If not, you should.
How much longer? Iām a busy man.
1 Like
I reckon the lack of heat (lower leaf temp) causes me to add 2 weeks.
1 Like
What is the difference is a complicated question. What is the difference between a cat and a dog?
In a functional practical senseā¦whatās your budget? Both can do the same job well. I prefer CMH.
Some major considerations with LED:
The unit can partially or totally burn out. Leaving you lightless while you wait a week for a new one to be shipped out, and you gotta return the old one. With HID technology, especially MH and HPS, if something goes wrong, itās either the ballast, bulb, or cord/socket. Replacement is fast, easy, and can be done the very same day after a trip to the grow store. Not so easy with LED units.
Upfront cost on LED is high. You can find used HPS lights for $100. It works, and well. It is less efficient.
CMH is more efficient but is between LED and HPS cost-wise. Bulbs last longer too.
No right or wrong answer. Iāve seen plenty of crappy LED bud, it isnāt necessarily a better light source. ālight penetrationā is kind of a marketing term IMO.
2 Likes
Hogwash.
I recently grew a plant that was ready in 49 days. So youāre saying with HPS it would have been ready in 35?
Somehow I donāt think so.
2 Likes
The only way to compare the both of them is watt for watt. For example 600w hps would have to be compared to an led that draws 600 actual watts from the wall. When they draw the same power from the wall the heat output is close to the same. The power usage is obviously the same when compared at equal watts drawn from the wall. And even at the same wattage I personally havenāt used any led that compares to yield and penetration of hid. But then again I never paid 2000 for a led light the highest I paid was 500.
2 Likes
No, I think it matters more with Sativaās, plants that are genetically prone to needing higher temps. I can not for the life of me finish those types of Sativaās in the listed number of weeks. They always seem to take 2 weeks longer.