All BS set aside CMH yields

is it true or not


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38Fitter

Member
So maybe someone can help me out here. I read this whole thread over the weekend and I still am unsure on how to most effectively utilize CMH.
My flower room is 10x10 and I'm about to invest in all new lamps. I have two 4x4 tables.
Per table, Should I use (3) 315w 3100k for quality and yield?
Or go with (2) 315w 4200k and on either side and one 400w HPS in the middle?
Any other ideas? Thanks everyone.
 

since1991

Well-Known Member
I would skip the 400 watt hps just for the fact a sixer is only 200 more watts and you get way more and better quality buds. I use to run 4 hundos myself way back in the day. Thought they were awesome but then i stepped up to the bigger wattage fixtures and it was no contest. 400 watt hps lamps have a purpose. Great for vegging and flowering as well if you bud out a bunch of smaller plants in a 3x3 area but for bigger setups...they just arent practical. The pros dont pack a big room with 400's for a reason. Back in the day we used to. Before 600 watters were even out yet. All we had were 400 and 1000 watt single ended bulbs and loud hot magnetic ballasts. And anyways ...blending a cmh with hps together seems to be the way to go. Yield and quality. I know what you mean though. You trying to get the perfect light plan figured out because its a one shot deal and pricey if you have to redo it. Try a sixer of hps and a 315 cmh over each 4x4. Just over 900 watts for each and your splitting the spectrum for the perfect blues and reds as well. Plus your initial buy in for the lamps is less. Packing a room that size full of all 315's is expensive. And for a lamp fixture that is still kinda new with all the forums and growers giving varied results. I was gonna buy 9 to 12 of them myself but changed my plan. Dont forget your air conditioning needs. Got to get the right btu rated unit(s) for the heat load.
 
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38Fitter

Member
I would skip the 400 watt hps just for the fact a sixer is only 200 more watts and you get way more and better quality buds. I use to run 4 hundos myself way back in the day. Thought they were awesome but then i stepped up to the bigger wattage fixtures and it was no contest. 400 watt hps lamps have a purpose. Great for vegging and flowering as well if you bud out a bunch of smaller plants in a 3x3 area but for bigger setups...they just arent practical. The pros dont pack a big room with 400's for a reason. Back in the day we used to. Before 600 watters were even out yet. All we had were 400 and 1000 watt single ended bulbs and loud hot magnetic ballasts. And anyways ...blending a cmh with hps together seems to be the way to go. Yield and quality. I know what you mean though. You trying to get the perfect light plan figured out because its a one shot deal and pricey if you have to redo it. Try a sixer of hps and a 315 cmh over each 4x4. Just over 900 watts for each and your splitting the spectrum for the perfect blues and reds as well. Plus your initial buy in for the lamps is less. Packing a room that size full of all 315's is expensive. And for a lamp fixture that is still kinda new with all the forums and growers giving varied results. I was gonna buy 9 to 12 of them myself but changed my plan. Dont forget your air conditioning needs. Got to get the right btu rated unit(s) for the heat load.
Right on. Thanks for the advice. I've got some 1k air cooled hps I used to run but I realize it's outdated.
What temp CMH should I use to supplement - 4200k for the blues?
And what fixtures should I go with? Verticals for the CMH no hood and an open horizontal for the 600? Any brands you'd recommend?
Price is not such a big deal, I've got a nice budget as I've been planning this for a few years now. Just finishing the remodel on this new house I bought and I'm ready to start the next project!
 

since1991

Well-Known Member
Right on. Thanks for the advice. I've got some 1k air cooled hps I used to run but I realize it's outdated.
What temp CMH should I use to supplement - 4200k for the blues?
And what fixtures should I go with? Verticals for the CMH no hood and an open horizontal for the 600? Any brands you'd recommend?
Price is not such a big deal, I've got a nice budget as I've been planning this for a few years now. Just finishing the remodel on this new house I bought and I'm ready to start the next project!
Some might say 1000 watt air cooled hps is outdated but the vast majority of American growers still use them. With double ended hps..you have to have high ceilings and alotof a.c. They are more for bigger commercial warehouses and what not. But if your combining a 600 watt hps woth a 315 cmh..I would go with the more blue Kelvin bulb at 4200k. Vertical for cmh. I like the Sun Systems 315 fixtures. And a horizontal simple bat wing reflector for the hps.
 

38Fitter

Member
Some might say 1000 watt air cooled hps is outdated but the vast majority of American growers still use them. With double ended hps..you have to have high ceilings and alotof a.c. They are more for bigger commercial warehouses and what not. But if your combining a 600 watt hps woth a 315 cmh..I would go with the more blue Kelvin bulb at 4200k. Vertical for cmh. I like the Sun Systems 315 fixtures. And a horizontal simple bat wing reflector for the hps.
Thank you. I really appreciate the advice. Seems to be in line with what I was trying to wrap my head around too. Cheers man.
 

Carolina Dream'n

Well-Known Member
So maybe someone can help me out here. I read this whole thread over the weekend and I still am unsure on how to most effectively utilize CMH.
My flower room is 10x10 and I'm about to invest in all new lamps. I have two 4x4 tables.
Per table, Should I use (3) 315w 3100k for quality and yield?
Or go with (2) 315w 4200k and on either side and one 400w HPS in the middle?
Any other ideas? Thanks everyone.
3x9 canopy down the sides. 6 315s. 3 ft walk way in center. 2 vertical bare bulb 315 in walk way.
 

38Fitter

Member
3x9 canopy down the sides. 6 315s. 3 ft walk way in center. 2 vertical bare bulb 315 in walk way.
Thank you, and while I didn't want to hijack the thread, I do appreciate the input as it's another question I wanted to ask.
I'm interested in maximizing my quality and it seems like the CMH will do that, whereas the hps will still give me the big yeild.
I'd like to go all CMH if you think it's worth it in the long run.
So you say - (3) 315w Phillips 3200k in a horizontal hood over each 3x9 and (2) 315w 3200k in the walkway to cover the edges?
 

MMJ Dreaming 99

Well-Known Member
3x9 canopy down the sides. 6 315s. 3 ft walk way in center. 2 vertical bare bulb 315 in walk way.
I would not walk into rooms when CMH's are on. Eyes and skin cancer. CMH are bright and throw off UV.

Another reason why I might prefer something like QBs is CMH bulbs need to be repalced and are not cheap.
 

TheChemist77

Well-Known Member
I would not walk into rooms when CMH's are on. Eyes and skin cancer. CMH are bright and throw off UV.

Another reason why I might prefer something like QBs is CMH bulbs need to be repalced and are not cheap.
cmh bulobs last for years,, unlike mh and hps were bulbs should be replaced every 6-8 months.. ive been using the same 315 watt master agro 3100k phillips bulbs for almost 4 years now,, no loss in yield,quality, cmh way better than hps,mh or both...
 

MMJ Dreaming 99

Well-Known Member
cmh bulobs last for years,, unlike mh and hps were bulbs should be replaced every 6-8 months.. ive been using the same 315 watt master agro 3100k phillips bulbs for almost 4 years now,, no loss in yield,quality, cmh way better than hps,mh or both...
Cool. I did not know that. Thanks bro.;
 

38Fitter

Member
Whe
cmh bulobs last for years,, unlike mh and hps were bulbs should be replaced every 6-8 months.. ive been using the same 315 watt master agro 3100k phillips bulbs for almost 4 years now,, no loss in yield,quality, cmh way better than hps,mh or both...
Do you supplement those 3100k with any 4200k for a complete spectrum?
 

since1991

Well-Known Member
Whe

Do you supplement those 3100k with any 4200k for a complete spectrum?
Your paying way too much attention to that kelvin rating for those particular fixtures. Either kicks ass in veg or flower. Very similar. Generally the 4200k for veg and 3100k for flower but either will do really well if you do your part. The cmh spectrum as a whole is vastly superior to any HPS for a sun like lamp...improving overall appearance and trichome/terpene development. Combined with HPS in flower your getting bigger buds than cmh alone as well. A good rule to follow..from what I have witnessed..is cmh for overall quality and health of the plant..combined with the fatness that HPS provides. Best of both worlds. But none of this means much if you let your climate (temps/humidity/co2) get out of hand and your starting genetics are whack.
 
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38Fitter

Member
Your paying way too much attention to that kelvin rating for those particular fixtures. Either kicks ass in veg or flower. Very similar. Generally the 4200k for veg and 3100k for flower but either will do really well if you do your part. The cmh spectrum as a whole is vastly superior to any HPS for a sun like lamp...improving overall appearance and trichome/terpene development. Combined with HPS in flower your getting bigger buds than cmh alone as well. A good rule to follow..from what I have witnessed..is cmh for overall quality and health of the plant..combined with the fatness that HPS provides. Best of both worlds. But none of this means much if you let your climate (temps/humidity/co2) get out of hand and your starting genetics are whack.
Ah, I was under the impression that utilizing the entire spectrum is where the best results come from. Thank you for clearing this up. It's really the CMH tech as a whole that's killing it.
 

MarWan

Well-Known Member
I would not walk into rooms when CMH's are on. Eyes and skin cancer. CMH are bright and throw off UV.

Another reason why I might prefer something like QBs is CMH bulbs need to be repalced and are not cheap.
From my experience

I bought a double ended 150w MH that is supposed to be used as security light, and used for vegging my plants and it did ok but I didn't like the light spread. For some reason I decided to remove the glass, as a result my plants started dying and I can feel strange radiation bothering my skin and eyes, so I got rid of the light.

Now I use CMH with no glass in the hoods, and my plants are thriving and happy, and when I get under the lights to work on my plants it feels like working under the sun at 2pm on the month of May.
 

MMJ Dreaming 99

Well-Known Member
From my experience

I bought a double ended 150w MH that is supposed to be used as security light, and used for vegging my plants and it did ok but I didn't like the light spread. For some reason I decided to remove the glass, as a result my plants started dying and I can feel strange radiation bothering my skin and eyes, so I got rid of the light.

Now I use CMH with no glass in the hoods, and my plants are thriving and happy, and when I get under the lights to work on my plants it feels like working under the sun at 2pm on the month of May.
MH is really bad and I hate it. I had two pre-cancerous spots on my skin that took off. Fortunately, I have some stuff that effectovely kills the cancer in 24 hours.

Be careful with CMH too.
 

38Fitter

Member
MH is really bad and I hate it. I had two pre-cancerous spots on my skin that took off. Fortunately, I have some stuff that effectovely kills the cancer in 24 hours.

Be careful with CMH too.
Care to share the formula? I have personal friends who've effectively used whole plants strained through Everclear to shrink tumors small enough to be removed....
 

TheChemist77

Well-Known Member
i have done lots of cycles using cmh 3100k phillips agro bulbs in both veg and flower. a 4x6ft f&d table.. 2 315's above gets `1.4 gpw,, but 3 315's over table really increases bud size and gets an average of 1.56 gpw ive even got 1.6 on a few..
my last 3 runs i now have over head 2 315 3100k cmh and 2 100 watt go green citizen cobs.. using 3 315's 945 total watts and getting 1.56 gpw,, now 2 315's and 2 100 watt cobs totaling 830 watts and im getting 1.54 gpw average..citizen cobs are also 3100k.. in veg i have 1 315 3100k and 1 100 watt go green citizen cob 4100k.. i have found the bigger the change in kelvins from veg to bloom the larger the stretch,, using the same 3100k bulb in both veg and flower really keeps the stretch to a minimum.. if going by gram per watt the mix of cmh and led kicks ass but if you dont really go by gpw and just want large top buds,, the 3 cmh gets very nice tops..
i plan on doing a run w 4 315's over the table,, i dont know if gpw will get any better than 1.6 gpw but i can tell u bud size will be amazing and uniform..
i grew w/ hps, mh, for 20+ years and i love them, 2 600 hps over my table always got 1 gpw,, 1200 grams,, but using 3 c315watt cmh my gpw is far better and bud size isnt very different.. anybody saying hps gets bigger buds than cmh is off,, top buds directly under the 315 are just as big as buds directly under a 600 watt hps,, only difference is the bud under the cmh is better potency and finishes a few days faster...
 

since1991

Well-Known Member
Those numbers are awesome. Wow. 1.5 gpw using less than 1000 watts of light? Damn thats great. Thats over 3 frikin pounds and not an hps lamp around. Amazing. Maybe combining COBS with cmh is where its at. I dunno. I do know my grow pals went all cmh..then cmh and hps combined. Numbers went up comnined. But sounds like you got your room dialed like a mo' fo'. Are you gassing co2??? What strain(s) are you running??? Net trellis? Plant count? A 4x6 flood table? Medium? What do you like your pH and ppm at in peak flower? Sorry for all the questions but those numbers are really good. Alot of work isnt it?
 
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kermit2692

Well-Known Member
Some might say 1000 watt air cooled hps is outdated but the vast majority of American growers still use them. With double ended hps..you have to have high ceilings and alotof a.c. They are more for bigger commercial warehouses and what not. But if your combining a 600 watt hps woth a 315 cmh..I would go with the more blue Kelvin bulb at 4200k. Vertical for cmh. I like the Sun Systems 315 fixtures. And a horizontal simple bat wing reflector for the hps.
Just meandering through the thread and wondered why you say he would need high ceilings and a big ac to run a double ender??
 
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