CMH vs LED
- Thread starter The_Dude
- Start date
Antitheist
Well-Known Member
Based from what I've read cmh is the best flowering spectrum currently available. Dense fatter buds is my experience. I just flowered a few under a 315 cmh. I'm gonna get another.
You can score a cmh cheap and replacement bulbs are $40-$100. That kind of money won't even get you started with a led. Not one worth having anyway and it won't perform as well as a cmh for flower.
You can score a cmh cheap and replacement bulbs are $40-$100. That kind of money won't even get you started with a led. Not one worth having anyway and it won't perform as well as a cmh for flower.
Lordhooha
Well-Known Member
I run mainly led however this run I’ll be using a 630de cmh to see the difference flower wise.
bigbudzzzz420
New Member
I use LED mainly
SunPlix CMH
Well-Known Member
Yes, you are right. All of customers found the same.
Hotwired
Well-Known Member
Would the 630de cmh with a Cool Tube Reflector work ok? Will the glass make that much of a difference? I really like this type of reflector and I think it would work better in my short tent.
https://www.homedepot.com/p/Hydro-Crunch-630-Watt-DE-CMH-Ceramic-Metal-Halide-Grow-Light-System-with-Double-Ended-8-in-Cool-Tube-Hood-Reflector-KDCMHR17-630-3K/304532641?MERCH=REC-_-rv_gm_pip_rr-_-304525860-_-304532641-_-N
https://www.homedepot.com/p/Hydro-Crunch-630-Watt-DE-CMH-Ceramic-Metal-Halide-Grow-Light-System-with-Double-Ended-8-in-Cool-Tube-Hood-Reflector-KDCMHR17-630-3K/304532641?MERCH=REC-_-rv_gm_pip_rr-_-304525860-_-304532641-_-N
SunPlix CMH
Well-Known Member
Don't put CMH bulb in a sealed hood such as the cool tube reflector, the glass will block most of UV light.
INF Flux
Well-Known Member
I've heard cmh is best used alongside a primary light system, be it led or hps, to provide uv and ir. Getting the growth rate as well as the higher trich production seems like a good way to go. Personally,I'm just going to get far red strips and a reptile bulb
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primobozo
Well-Known Member
Just switched to cmh from led, I have a 315w and a 630w both with the Phillips 3100k, the led's gave me great bud, frosty, dense, but never huge. With the cmh they're getting fat as hell. Plus frosty. I'm not knocking led's, the reason I switched, is over warranty issues. Usually ( if you read the fine print ) the company gives you actual wattage. Yes even the diobolical Chinese one's. But after buying 4 blurpies for a true total of 954w I lost 6 rows of led's (All lights from same manufacturer ) on 1 of the lights, after 2 months of emailing the company to try and get a replacement panel with no response, with a 3 year warranty, ( yeah right ) I got pissed and bought the cmh lights. Wished I got them from the start. Now I get dense, frosty, bud's that are huge. I'm not bitching about the led's, and I still use them the last two or three weeks of flower to up my UV and IR, but I love the way my plants are doing under the cmh. I'm only talking about the cheap led's, hlg and nextlight put out great lights. But they are out of my price range. For the money I'm going to stay with the cmh. I'm currently switching to dwc from soil, and the learning curve is a bitch, but I want bigger and better, so it's a journey, like most things in life.
jordanwh
Member
For quality flower under a CMH, for yield use HPS. Im vegging under a CMH and it’s working wonderful.
I don’t have great genetics at the moment so quality isn’t on my mind plus I’m growing some Power Plant right now so I’m looking to maximize my yield on an already heavy yielding strain, even though I’m vegging with a CMH in a 4x4 when I flip them it will be a 600w HPS.
AllThingsGreen
Member
So I’m necro-ing this thread. I’m in the market for a HLG 260w XL for my 2x4 tent. I’m kind of holding off because it’s a 400 dollar light, but I want to get away from these blurples. Without getting bro-sciency, if I get a quality Cmh fixture could I expect similar results (quality wise this is all I care about) from a Cmh vs a HLG LED fixture ?
coreywebster
Well-Known Member
Not going to go into anything other than light spread and footprint. The HLG covers a 4x2 (you dont need the XL by the way)
The 315cmh covers a 3x3. Although technically both cover the sqaure footage the HLG would be a better light spread.
Im sure you would have good results with the cmh, just might be a bit wiffy in the far reaches of the tent.
coreywebster
Well-Known Member
https://horticulturelightinggroup.com/products/260w-qb-v2-led-kit
The standard (non XL) v2 260w kit. $330
The standard (non XL) v2 260w kit. $330
SunPlix CMH
Well-Known Member
This light works with both CMH and HPS bulbs.
When you need quality, use a CMH bulb, and when you need yield, use a HPS bulb.
https://www.sunplix.com/product/1000w-knob-dimming-de-hps-mh-cmh-low-frequency-square-wave-grow-light-fixture/
When you need quality, use a CMH bulb, and when you need yield, use a HPS bulb.
https://www.sunplix.com/product/1000w-knob-dimming-de-hps-mh-cmh-low-frequency-square-wave-grow-light-fixture/
AllThingsGreen
Member
I was picking the XL because the larger heat sink spaces the lights out better. I would also still need red and UV supplement with QBs but CMH would be an All in one solution. I think I’d be ok with a CMH vs the QB. I’m guessing QBs are pound for pound better than Cmh ?
coreywebster
Well-Known Member
Needing the UV or IR is a matter for debate.
QBs been better than CMH is also a matter not yet settled.
I love my QBs and the results are great, my cmh i veg with because its a great light for anything but i dont flower in 3x3 spaces so it wouldnt suit my flower tents. It does cover a 4x4 in veg durin summer though.
CMH is a great spectrum, just not right for my situation.
Like i say for the footprint to cover a 2x4 i prefer the QB due to the shape and the way that distributes light.
I think you would be impressed with either light.
