LED grow lights

sfhaze

New Member
The prices are still way to high but I'm interested in the technology. The ledtronics plantbar5 looks like a great product for cabinet use.

Looking at growing in a 17" by 36" utility cabinet on two shelves. Hopeing to grow up to 20 small plants (24" tall or less) by going to 12/12 very early, or right away.

The vendor claims the LEDs are so bright that the correct distance is 18 to 24 inches above the plant. They claim that any closer will just stress out the plant from to much light and halt vertical growth.

Well at 18" the seedlings just stretched out like crazy, clearly that is to far. Trying various heights it looks like 4-5 inches is about right to keep the proto-leaf of a seedling from stretching more then about an inch above the soil. Isn't that about what I want? How high does the proto-leaf normally stretch out above the soil for a new seedling?

Also, if you start seedlings at 12/12, how do you prevent them from stretching like crazy if they come up during the 12 hours of dark? Do you run the lights 24 hours at least the first few days?

The 18 to 24 inch recommendation would of been a problem anyway, so it's not really a show stopper but when you are at 5 inches it doesn't look like the colors from all the different LEDs completely blend, but it's not that bad.

I was kind of hoping that 2 plantbar5's per shelf would be enough (based on the vendor's claims) but based on this it looks like 4 per shelf would work a lot better, which makes this $2000 for the lights. Also, I don't think the plantbar 3's would be useful. Clearly too expensive for most people right now but there are a number of advantages. The biggest one is the power savings, but it also is a lot safer since there isn't any high voltage.

The other issue in general is that there isn't enough heat, so adding heat pads under the pots is helpfull.

Here is the power budget:
8 plantbar5's (4 per shelf) - 80W
Ventilation fan - 44W
2 heating pads - 50W

Total is 174W going 24 hours

When switching to 12/12 would you keep the heating pads on, or turn them off also?
 
My first question would be, do you have a strain that can finish less than 24" tall? Even if you switch to 12/12 quickly, 24" is not much space. Are you scrogging them? Hydro or Soil?
 
Yes, they are small indoor strains and should handle it.

Scrogging would work but this is more like the nomercy straight 12/12 idea with lots of small plants. It's soil, each plant is in a 5" square pot just under a gallon. Only expect 0.25 to 0.5 oz per plant, but times 20 plants it's not bad.
 
Sounds like it should be an interesting grow. I don't have any experience with nomercy's system, so can't contribute much there. But, I would turn the heat pads off once you switch to 12/12, unless it's too cold for the plants. As someone looking into LED's as well, please post a grow journal on this when you start- you'd be doing everyone here a huge service.
 
You may have to snap them down if size becomes a issue.. IDK about bud size per watt ratio though ?? Adding CO2 to the cabinet if your lighting is lacking cause of space/heat issues it can help pick up some of the slack on bud development from my experience.
 
The seedlings mostly stretched but haven't tried starting closer then 6 inches, I think 3-4 inches would work. The seedlings started on flouresent (1 inch from the tube) and then moved to leds are growing well at about 5 inches below the leds without to much stretching. Maybe there is just some issue with seedlings.

The stretched out seedlings fell over, so I just curled them up and buried the stem up to the proto leaf. They seem happy and are still growing.
 
The issue with the seedlings stretching with the plantbar5's seems to only be with seedlings. Plants started under flouresent grow normally. Also, going any closer then 5 inches does stress out the plants, they wrinkle up a little. The 18 inches the vendor recommends I still think is to far, so right now I think optimum is 6 to 12 inches above the tops. I'll try a seedling at 4 inches, just to see if it doesn't stretch but think I will start seedlings on flouresent from now on.
 
It seemed like I was always running into potential cultivators who had given up on the idea, mostly due to the issues with working in close spaces using a 400HPS. The only indoor alternative is LED. After reading all the pros of using LED, I decided to risk a few generations of WW for testing.

Obviously, there are no standards yet and LED’s are not all the same. Anyway, I separated the two cycles (18 Blue Only vs 12 Red Only). There is still soooooooo much to learn, but here’s the results I’ve seen.

The bulb: (flood light) provides a more concentrated and focused light that weakens at 2” from as outer rim. The Panel: I use custom 12” x 12” panels that provide light uniformity to 19” x 19” at a 6” height.

Height management is more difficult with the bulbs unless you use a light tree to illuminate lower branches in the corners of the grow tray. Generally, the panels works best for me at 6” to 8”. Anything closer seems too stressful and heights above 12” sent my seedlings into stretch mode.

As for ticks… I converted a 5’ x 4’ grow space, originally using 3 - four foot fluorescents (mixed cool/warm) with 16 -12” x 12” panels. I positioned 8 panels in 2 horizontally rows above the plants. I then positioned 4 at a 45 degree to the left side and the other 4 on the right side also at a 45 degree angle. From the outside, it looks like one massive light hood being held by a spider web.The entire light unit is raised and lowered using a single line for ease.

Outside of being blind every time I walk away from the grow tray, the most visual result is wider plants. I was using 18” off center, but I can get about 22” to 24” now. Best of all, the entire light system only pulls 272 watts and temperature is not a problem. I’ll keep you posted with new results as they come in.
Oh yeah, it did cost about $900 for the light setup but hey it's good for 3+ years.:smokin:
 
I forgot to mention an important note. I originally used 5 mm, 470 nm (blue wave length), 15 degree viewing angle, round LED’s. At this viewing angle, I was able to get LED’s with a mcd (luminous intensity) of 5500. Cost: $0.87 each.


I since replaced the LED’s with 5 mm, 470 nm, 120 degree viewing angle, flat LED’s. My mcd drop to 1200. PROS: More uniform coverage. CONS: Less intensity. However, at 6 to 8 inches distance between LED and plant, you never have to worry about stressing the plant. I now pay about $0.39 each.

If you have the time and want to cut your lighting cost in half, build your own LED panel.
 
The ledtronics plantbars have been a bit disappointing. Plants grow slowly and seedlings stretch even when very close. I added some of the "grow with LEDs" Smookin Moose pointed out along the sides and they are a lot brighter and I'm seeing the growth rate I wanted. The spot lights take up a lot more depth and aren't as safe but they cost less and work a lot better. The plantbars would be real good for cloning but just don't have the power to do the main flowering.
 
The most mature plants are now on the 5th week of 12/12 and are doing well. The tallest is 18 inches, there is about 23 inches max so it's going to be close but should be okay. There is really only room for 8 plants per shelf (16 total).

I ended up with 3 plantbar5s in the middle plus 4 90 diode xb red and 2 90 diode blue spots on the sides, about 60W total per shelf. The heating pads are no longer needed since the lights are warming things up just a little.

Overall the system seems like it will work well, it's easy to move plants around verses scrog. There is just the main branch and no side branches, it's like just growing the main center stem (always the best part). It allows lots of experimentation since more plants are growing.

The 4" inline fan works well with a "ordor sok" carbon filter controls the odor completely, at least so far.

The nomercy system uses 12/12 from the start but that can cause the seedling to stretch to much. One solution is just to bury the stem some when transplanting into the main pot but that doesn't work for me since I'm trying to avoid transplanting and start the seeds in the final pot. After about a week the seedling can tolerate lower lights and long nights. I've been starting the seedlings in a separate space with 24/0 cycle. It take 3 days to sprout and then 11 days at 24/0 before moving them into the cabinet.
 
there are more reasonably priced led's. check e-bay. there's a couple of companies selling 225 led red/blue spectrum panels, 14 watts for about 40$ a peice. the bars and "ufo"s are definitley pricey, but remember at any price the leds use a tiny fraction of the power of hids or hps. and they last infinitley longer, so they should save money after the investment.

i'm trying to grow with very little power use, ( my first time ) i used 4, 20w cfls for seedlings, now using 8, 20w cfls for vegetative, and plan to use 4 of these panels for flowering.

i'd love to hear if anyone else has tried them
 
there are more reasonably priced led's. check e-bay. there's a couple of companies selling 225 led red/blue spectrum panels, 14 watts for about 40$ a peice. the bars and "ufo"s are definitley pricey, but remember at any price the leds use a tiny fraction of the power of hids or hps. and they last infinitley longer, so they should save money after the investment.

i'm trying to grow with very little power use, ( my first time ) i used 4, 20w cfls for seedlings, now using 8, 20w cfls for vegetative, and plan to use 4 of these panels for flowering.

i'd love to hear if anyone else has tried them

I haven't used them yet but they have definately caught my eye. Right now they don't seem to be as "good" as HID. They're still a relatively new product, It's gonna take some history and good reports before I'd even think about getting rid of all my HID lights and investing that much money into a new product.

BTW, The lights don't last forever. I've read from one site they have roughly a 7 year lifespan and another site has them listed with a 3.5 year lifespan. Granted, That's still ALOT better then HIDS which usually last between 9-12 months before they are recommended to be replaced. High end bulbs can cost between $90-$120 not to mention the cost to run HID lights. Hopefully one day HIDS will become a thing of the past but for right now you can't beat there power IMO.
 
The ufo is billed as being equal to a 600watt HPS with a fraqction of the power and no heat. I myself have never seen one but wouldn't mind trying one or two out. As for life span...when you replace a HID bulb you replace "1" bulb, not 225. Plus I wonder if they even sell replacement bulbs. I bet you would have to replace the entire unit. I'll stick with HID's until these get used by more and there are more reports out.
 
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