Basement grow buildout - LED vs HPS DE vs 315w CMH? 7.5’ ceilings

i know theres a lot of great growers on here. would like to get yalls opinion on a basement buildout. I have the oddly shaped room you see in the attached pics and im trying to maximize footprint canopy and yield in this next room. i already have a bunch of phantom 1kw DE’s but im second guessing running these versus going 315w cmh. i could run 12x 1kw DE’s on 5x5 footprints or 33x 315w CMH on 3x3 footprints.

How do the china CMH setups compare to name brand? ive noticed with 1kw DE setups a china lamp and bulb is not noticeable yield and quality of flower wise compared to a gavita with an ushio bulb. is this true of 315w cmh setups as well? would probably look to get all these lamps on alibaba with 0-10v controllable and bulbs.

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If you run 1k DE’s with 7.5’ ceilings, you’re gonna have a bad time. I kept mine 3’ from the canopy or risked bleaching and foxtails from heat stress. You are also going to need 3.42 BTU/actual watt and a ton of air circulation to cool it properly. That’s some HVAC horsepower with such low ceilings.

I would go with the 315 CMH. 3x3’ footprint is 35 watts per square foot- a little low for flower. 2.5x2.5 is 50 watts per square foot, the upper end.

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I have an 8x12 flower room. Sealed, co2, 4x 315w cmh in ac hoods.

5x10 veg tent. 2x315w cmh plus 4x 4 bulb t8 led on sides of hoods.

8x10 clone room. 6x 4 bulb t8 led.

1k de need a 10’ reclining as those fkrs run HOT!

Footprint is 90% dependent on the hood. I can manipulate light with different hoods. Think of it like a mag flashlight. Smaller hoods = more focused light spread. Bigger hoods = more spread out light, but loose depth.

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I’ve chatted with @Demontrich about hoods before. He’s absolutely right about getting the proper hood for the footprint. Once you pick out your hood, you want it 500+ ppfd for flower based on height above the canopy.

I tend to throw out a lot of formulas, but once you get the equipment, you dial it in for the space.

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I have been operating with a significant sized “basement grow” 7’5" ceilings for about 5 years now and I can tell you that LED is the ticket for me. I did try a SunSystem LEC 630 and due to the extreme heat produced I took it down after about 4 hours. I run two portable 14,000 BTU air conditioners with exhaust/dehumidifier and that one light increase the room temperature in that short amount of time by 11 degrees… too hot for my taste. I also could tell in advance that it would require way to much distance from the canopy to even begin to be useful. Check out the Grower’s Choice ROI-E680 LED. It increased my yield by almost 40% from the KIND K3 L600. I am now in the process in gradually changing out 22 of those KIND’s for 11 of the Grower’s Choice ROI-E680 LED

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this will not be sealed I will have a similar exhaust/enviro controls as my other rooms. I plan to mount the DE’s to the cielings and scrog the canopy down low. but i have thought for a while running 1kw De’s down here would cause crazy exhausting cycles far worse then my other rooms since the ceilings are lower.

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man LED is a no go for me, i would end up running HLG quantum boards but i dont have the money to outfit this room with quality LEDs.

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Led… dont even get me started on that garbage.

I make 1k users cringe at what i can pull from 315 cmh. And I absolutely LOVE rubbing it in their faces when ever I can!

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ive actually ran 4x 1kw DE’s in a 10x10x7 tent with great success down in this basement. the trick was to scrog down low.

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there’s really only 2 hood styles on alibaba to choose from (in order to keep costs down) “open” and “enclosed” the open hood basically spread the light out quite a bit, the enclosed hoods focus the pattern more

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I know you think CMH is the best and maybe it is but until you have grown a side by side comparison with the exact same strain from the same mothers using strip/bar LEDs you do not know and can only assume. I have read your posts and I know you tried COB but I also know you have not tried the style that @MTOG mentioned. I don’t use that brand but I do use Sunplix 10 bar which look pretty close.
BTW I have seen pics of your grow and its clear your shit is dialed in and looks killer.

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Enclosed is a glass bottom hood, with or with out ducting that can be blocked off with the supplied plates (big kahuna comes with ac stacks and cover plates.

Open hood is just that. No glass, no ac option. All heat stays in room and makes ac work much harder.

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I’ll gladly drop big $$$ on the gavita 1700e IF and only IF it will produce more weight, AND not kill my ac with the heat.

Cost is negligible at this point.

Fluffy garbage buds need not bother. I grow rock hard nuggets.

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I’m speaking in DE reflector lingo. Both styles are open bulb style. I’m not planning on running any air cooled style reflectors they will be open bulb.

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You looking at buying new 1k systems or just retrofit new hoods. I run a 1k DE setup thats a wing style reflector. Its very light weight and can literally be attached to the ceiling for maximum spacing.

I’d go with the quantum board leds like you mentioned. I use both leds and de hids at my grows, they both have their places. I know demon loves the cmh but from me when I did my side by sides led beat them out overall. Cost was not a issue I am looking for quality buds and yields. Both the led and cmh have great some but the yields on the cmh weren’t there for me nor was the penetration. demon mentioned his yields in the other thread not trying blow his spot up, for me I saw similar to his not as good though but close with 315s. With leds 1 gpw is easily attainable I’m Currently hovering in the 1.5 - 2 gpm in my led rooms with friends that have similar dialed in setups constantly pulling 2-2+ gpw. It all came down ease of use/ lifespan the outfit cost is very similar. I was at 3 x 315 over a 4x8 vs 2 hlg 550 in same space. Using demons no His shit is dialed in that be 3 Lbs vs my 3.5 -4 lbs using leds. Really the main issue I had with my cmh was I would keep loosing bulbs randomly, it’s a complete bitch to change out bulbs when my rooms are scrogged wall the wall. Can’t stand in rooms. I wouldn’t use 1000 de in your setup just for heat and light burn the 600-750 de were made for 8ft under ceilings.

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I’m sure it would be worth buying just 1 to compare if you could sell it for 1/2-3/4 price if you don’t like it.
There is a reason that Gavita has moved into the LED bar market and also take note they call that LED the future. I can tell by your pics you grow awesome shit so no doubting that. I am guessing the biggest reason bigger grow operations use CMH over bar LEDs is the original cost to set up the space. Proof right here by the OP.
Not sure why your worried about heat from bar LEDs when your running CMH.
I know growers that use CMH and no comparison to the heat output. I have never used CMH and I have been growing over 20 years.

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I’ll take 5 at 30% off for the gavita pro 1700. I’ll pay full price for the gavitabpro controller.

I’ve had 1 bulb burn out early. And Philip’s says 20k and 30k hrs of use. Sure it may/can light for 20k-30k hours, but I’m sure not worth growing plants for that many hrs. I swap mine after 3 or 4 10week cycles.

Also, any hood can be retrofitted with a de socket.

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Well, if the cmh are in air cooled hoods, you can keep most of that heat out of the grow space.

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