[SimonSez707]

Hey all,

Just finished my first run with 4 LEC 630W fixtures. They were the nanolux brand dual 315s. Even with a couple plant issues (including pretty much losing one light to herms) and some burn, the 3 lights with viable cannabis under them produced 4 pounds. I was extremely impressed with these results especially seeing that the plants were not perfect and we could do even better!

Anyway I just wanted to start more of a master forum about growing under these types of lights. What have you learned? what are your results? What questions do you have and so on...

Currently we Veg under the LEC 4K bulbs and flower under the 3K bulbs.

I'll start the forum off with an initial inquiry. Has anyone seen the plants flinch or not respond well from moving them between spectrum bulbs. Just like in the example of my grow, from 4K-3K? Or from 2 630s to spreading them out under 4 630s? We do veg under the 3k for a week before flipping as well. Next round we will only spread them out under the 2 3K lights before turning on the additional 2.

Anyway just thought I'd get this party started. Contribute what you can. Blessings.

[Boyd Crowder]

no idea about cmh lighting but ill sub and see what you got for us

pics or it dint happen

[SimonSez707]

No Pics Last round. Unfortunately I have a flip phone still and the photos it takes are pretty grainy. Hoping to get a go pro going at some point though. If I do I'll definitely take some pics of this next round. They are on day 3, same set up although we are adding a four bulb T5 with replacement LED flower spectrum bulbs into the corner where it's a bit shady and we have a couple extra genetics we are testing .

[Phaeton]

I put in CMH the same year GE came out with their Ultra Max square wave ballast. The light has the best full spectrum balance I have found in the retail market.
But.
The light cannot be efficiently focused, no matter the reflector used, between 50% and 75% of the light is wasted. A 60 degree beam LED only wastes about a third, which is a real improvement.
But.
No infrared and not enough far red in LEDs, and neither CMH or LED contains proper UVB. Except Lumatix and their all UV $500 unit putting out 100 watts.

As a commercial grower since 2001 I have found using several sources of light gives the best combination of quality and rapid growth.

LEDs give the most growth per watt if the correct spectrum is used. CMH gives the best quality if intensity and temperature can be controlled. T5 fluorescent's are the only economical source of UVB at this time.
UVB seems essential in producing "creeper" weed, the stabilizing chemicals the plant uses for protection slow the absorption and metabolism of THC resulting in a slower onset and longer duration.
Far Red makes for solid buds and no hermaphrodites, the fixtures only became affordable in 2015.

The thread is labelled as tech, so:

The mix of lights at the currently affordable level is
Overhead grid:
CMH, 4000K, 10,000K, 1400 watts.
LED, mix of 'white' and single wavelength diodes, 3120 watts.
Side surround:
LED, passive with 144 watts of Far Red 'twilight' feature, 1500 watts total.
LED, Far Red stand alone, 200 watts.
T5, UVB, 324 watts of 10% UVB.

The 9' by 7' area is a five plant perpetual, harvests are twice a month.
When using high yield clones dialed in accurately the yields were 12 to 14 ounces per container (18" dia x 9" deep), two to five plants per container. About a pound a a half per month.
With seed plants the yields are 6 to 9 ounces per plant. Seed plants do not like to be in the same container so the monthly yield is under a pound per month.

That is the lighting and yields. Quite a few rooms and side by sides were done over the years.
No single source light met all the needs of marijuana plants. LEDs have no heat, HIDs have no efficiency, Fluorescents have huge gaps in spectrum and no efficiency.

Using the strong points of each blended over and around the plants cost just over $14,000 USD two years ago. This is a huge initial outlay, a similar set up in 2011 cost $17,000 USD so the price is coming down. I have found the useful life of LEDs to be four years. Both the CMH and Fluorescents get two years.
Bulbs are way cheaper than LED fixtures.

The photos are the bud room, the CMH is clustered at one end and the LEDs cover the rest. Side lighting surrounds the whole area.
The plants are mobile and moved towards the CMH as plants are harvested and new plants introduced.
The efficiency difference of CMH has 1400 watts over a single plant versus the LEDs using 3120 watts on four plants and still getting equal growth, hence the use of both. The quality of CMH buds justifies the high wattage, 600 of which is 10,000K finisher.

[positivity]

Spectrum and lux, that is all. Par is for advertising.
Cmh does it the easiest.
Nature of par is to exclude wavelengths. Par can take a hike.
They have a new par now, forgot the new name. I guess the old one wasn't accurate
Careful whose bible who read.

This is mostly for those looking to grow good herb easily. For setting yield records look elsewhere....parph..... Photosynthetic active radiation producing hay

Kinda kidding and kinda not

Have a good weekend..and don't take this post too seriously

I'll try and contribute a little to this thread when I have more time. Cmh is a really good light, probably the best for a small grower trying to grow his own plants/meds indoor with one light

Peace

[DemonTrich]

I swapped out 6x 600mh/hps for 7x 315 cmh and will never look back. I get KILLER yields. 3.5 from 4x 315 for the last 4 runs.

[moose eater]

Using enclosed 4'x4'x6-1/2' to 7' cabinets with axial 'muffin fans x 3 Up high and centered on 3 sides, and intake vents on 4 sides, I previously reached 1.25+ grams per watt with the better producers (in excess of 1.25 ounces/sq. ft.) using 400 hps for flowering. Two axials run on light timer per box, with one running 24/7 for air circulation in down time.

One box is 3.5'x3.5' and on casters, to permit mobility.

Boxes are painted inside with 'bright pure white' kitchen and bath latex enamel, quick-drying, low/no VOC, in either flat or satin finish. (*I've had good results in both cases). Having the light contained as it is, means light often lost to the nether-regions is reflected back onto the plants for better use of the energy used.

On the advice from an acquaintance, I switched to 315 cmh, and decided on the remote hood by Sun Systems (vertical bulb position), as they have what appears to be a better angle to the internal reflector, allowing for an ever so slightly more broad foot-print for the light than the Hydro-Farm LEC hoods do.

I'm currently shopping for PAR38 or similar in a flood-type LED, to suspend by stout lamp cord, through eye-bolts, in the corners of the ceiling of the box, as the lesser foot-print is visible to me.

Found some LED PAR38 plant bulbs on-line that, though a bit pricey, claim a far red spectrum.

Most of the PAR38 grow bulbs I've seen on-line either lack reviews altogether, or have questionable reviews.

[SimonSez707]

Anyone have an idea the right distance away from the top of the canopy for LEC 630s? I've heard 2' and just recently 4' . I can keep the temps down regardless because we have plenty of AC just wondering if the burn I saw last run from having them too close.

[moose eater]

I'm keeping 315s any where from 14"-20" for the most part. The only cabinet I saw anything that might have -initially- looked like burn was further distance than that, and likely was a combination of dying foliage/leaf in the tip of a ripening bud, nutrients, and/or ???

Other than that, everyone's happy as clams at the moment!

[clown baby]

anecdotal:

switched from 4x 600w HPS's to 4X 315w ceramics and am happy with the move. Not going back to HPS. Run cooler, smaller fixtures, same yields.