All BS set aside CMH yields

Discussion in 'Grow Room Design & Setup' started by Darth Vapour, Sep 24, 2015.


is it true or not

  1. yes

  2. no

Multiple votes are allowed.

    ganja361 Well-Known Member

    The really nice thing about ceramics is they are so good at bringing out colors and terpenes you don't have to cool the room to bring the traits out. I ran C02 until week 6 and 85 degrees and I had colas so purple they were turning black. After I turned the gas off I'm running 75 lights on and 65 lights off. It's been getting cold in Portland so even have turn the heat pump on sometimes.
    since1991 likes this.

    since1991 Well-Known Member

    Iam in Michigan. Freezing cold outside this time of year. I have a louvered intake that i strictly use for this time of year. I shut off my mini split the whole winter. I thought it crazy to run the room with the split on these months when its 25 degrees or lower outside. Saves me bucks. I have a six inch inline blower hooked to a simple themostat hooked to the louvered duct flap. Keeps it just as cool as the split...virtually no money spent. But anyways...sounds like a bunch of lec 's are going to replace my Gavitas...soon....real soon. It makes so much sense. And really..the whole hps spectrum from the very beginning was meant for fruiting crops in a greenhouse. Where the blues of the sun was plenty and the reds needed supplement. Makes sense that people are seeing improved crop quality totally indoors with lec spectrum. We used hps all these years because thats what we were told first off. All we had second (besides mh). And thats what gave us plump buds. But the whole hps spectrum was never ideal for the only light source.
    Last edited: Dec 30, 2016

    ganja361 Well-Known Member

    I would too but I like to keep my room sealed. Plus you have to if you're running c02. Or at least to best of your ability. Unless you like refilling tanks everyday.
    since1991 likes this.

    since1991 Well-Known Member

    I do use more co2 with the cold air intake in winter...but not by much. The intake louver opens up but sporadically. It drops the temp quick..then closes back up. I lose some co2 but its negligible at best. And worth it to not have the split running..throwing cash to the man every month.

    Chillums Well-Known Member

    Sorry to revive an old thread, just thought someone might be interested in my experiment. I wanted to know if I could run cmh's on standard high frequency electronic ballasts as there wasn't sufficient information out there pertaining to that.

    -2x400w hps
    -wing reflector
    -air cooled glass diy enclosed top
    -adjustable ballasts run at 300w(for 315 cmh)

    Lights ran without issue for two days. Then on the third day, as I was in the next room watching tv; all lights, tv, stereo all shut off for roughly five seconds before powering back on. I immediately checked the box and found the lights off. Everything else had turned on and worked fine except the lights in the flower box. After checking all breakers, fuses, panels and connections I switched the cmh bulbs for the hps; fired up no problem. The cmh bulbs are intact without any apparent alteration and no breakers blew there having been four between bulbs and main power. So I am inclined to believe the bulbs overheated emitted an EMP temporarily shutting off power to the rest of my house without damaging anything.

    p0opstlnksal0t Well-Known Member

    Has anyone used one of these DEva setups yet?
    since1991 likes this.

    Kushman077 New Member

    Did you ever get a chance to record your harvest results??
    Last edited: Mar 8, 2017

    ganja361 Well-Known Member

    I did. I got 4200 grams on 5 lights. Came out to 1.33 gpw.
    disbeverk and GroErr like this.
    Bad Karma

    Bad Karma Well-Known Member

    I have all square wave ballast LEC's. When there is a black out/brown out/power failure in my neighborhood it takes the lights 20-30 minutes to comeback on line. I'm not sure if it's part of the design of the bulb, or the ballast, but LEC light will not strike when hot, thus the built in cool down period. I wasn't sure if you were aware of that, or not, so I thought it was worth mentioning.
    MMJ Dreaming 99 likes this.

    ganja361 Well-Known Member

    It's the ballast. New technology to save the bulb. That's why the good ballasts simulate a sunrise so to slowly warm the bulb.
    febisfebi and Bad Karma like this.
    MMJ Dreaming 99

    MMJ Dreaming 99 Well-Known Member

    PM me bro.

    davidcup Member

    Very good result no? Do you think it can be improved?


    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.
    Last edited: Sep 25, 2017
    MMJ Dreaming 99 likes this.

    38Fitter 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!
    since1991 likes this.

    since1991 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 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.
    MMJ Dreaming 99 likes this.

    38Fitter Member

    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.
    since1991 likes this.
    Carolina Dream'n

    Carolina Dream'n Well-Known Member

    3x9 canopy down the sides. 6 315s. 3 ft walk way in center. 2 vertical bare bulb 315 in walk way.
    MMJ Dreaming 99 likes this.

    38Fitter Member

    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

    MMJ Dreaming 99 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.

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