HLG 600's and leaf burn

[Kassiopeija]

This post clearly illustrated the notion that high power bare diode board LED's are "hard on plants". There is a very tight parameter on conditions that all have to line up like stars in the sky for things to go just right. Stray slightly out of that golden zone and things go bad quickly.
How this has become the new norm and go to lighting is beyond me.
I suppose growers just enjoy problem solving?

to be fair, common sense would dictate not going to extremes like 200-800ppfd forth n back like black n white...

but then I have yet to see such fried plants to see from the sun - which is actually stronger (in ppfd) and oftentimes will even reach seedlings leaves for a long time.
(though outside an adaption phase is very very likely)
only vegged indoor plants put right into the direct summer sun will loose its leaves....
it's something with the spectrum... indoor lamps can be quite demanding esp. on tops

 

[jimihendrix1]

to be fair, common sense would dictate not going to extremes like 200-800ppfd forth n back like black n white...

but then I have yet to see such fried plants to see from the sun - which is actually stronger (in ppfd) and oftentimes will even reach seedlings leaves for a long time.
(though outside an adaption phase is very very likely)
only vegged indoor plants put right into the direct summer sun will loose its leaves....
it's something with the spectrum... indoor lamps can be quite demanding esp. on tops

Putting indoor plants in direct sun, often fries them because theres no UVA/B inside, unless one gives it as supplemental lighting.

 

[Kassiopeija]

Putting indoor plants in direct sun, often fries them because theres no UVA/B inside, unless one gives it as supplemental lighting.

yes, like I wrote

only vegged indoor plants put right into the direct summer sun will loose its leaves....

things is, why aren't young gardensprouts fried outside at 1600umol in cloudless spring days

 

[grotbags]

This post clearly illustrated the notion that high power bare diode board LED's are "hard on plants". There is a very tight parameter on conditions that all have to line up like stars in the sky for things to go just right. Stray slightly out of that golden zone and things go bad quickly.
How this has become the new norm and go to lighting is beyond me.
I suppose growers just enjoy problem solving?

come on now, this post only illustrates that the op has had issues with these lights in his circumstances, there are thousands of people killing it with "bare high power diodes"...

im not saying there isnt room for improvement in the "standard" led spectrum, there definitely is. more manufactures should stop chasing outright efficiencey and start thinking about spectrum a bit more.

but to suggest the op's problems are somehow the new "norm" for led growers is crazy talk and clearly not true...

 

[hillbill]

There was no air circulation or ventilation interruption?

 

[Blazin Budz]

So I dealt with this same problem with my HLG 320W XL QB's which I think have the tightest diode spacing of any HLG light. It got to the point to where I would never recommend Quantum boards to anyone. Its not only the intensity but the light spread makes it damn near impossible to maintain an even canopy in bigger set ups. I also have 7 ft ceilings in a sealed room. But since I had no extra money, I was determined to make them work.

Heres a list of all the things I did to resolve the issue.

1. If you're in organic soil, you need bigger pots or even more preferably soil beds and a way stronger soil mix than what you'd use under HPS. Organic soil is probably the hardest way to grow under quantum boards. These LED's just eat up so much nutrients its crazy. I switched to Coco and feed synthetic nutes at 2.5-3.5 EC now.

2. VPD. You need to dial in your VPD. I bought a Pulse pro to help with this but its not necessary. Get a laser temp reader off amazon and take your leaf temp. I run my room at about 85 degrees to get 82 degree leaf temp and I run 70-75% humidity in veg through about 28 days of flower. Once I get decent bud formation, I start lowering the temps and humidity until i get around 75 degrees and 60%RH.

3. Slowly raise your light intensity. I mount my boards to the ceiling and slowly raise the intensity throughout the grow. I never adjust board height.

4. This might be specific to my setup but ill mention it because it was a game changer. I used to use CO2 Tanks and an autopilot CO2 controller and CO2 tanks. I was going through a 20lb tank in about 7 days which was a pain in the ass always switching out tanks. Turns out there were 2 problems with the Autopilot controller. The first problem was that it just wastes CO2. Its not an efficient controller. The second problem I had was that the shut off switch would crap out if my tank was empty and it kept trying to switch my regulator on. I went through 3 autopilot units before I decided that I absolutely hated it and upgraded to a GreenAir CO2 controller. At the same time, I decided to buy a CO2 burner. Once i had the set up hooked up, I was going through a propane tank about once a month. But my plants would still burn easily under low PPFD and I had a lot of problems my next run. I was convinced I had a severe fungus gnat infestation. Well one day i unplugged the CO2 controller when I was working on some things and forgot to plug it in. I came back the next day and the plants were the happiest i had seen them the whole run. To shorten an already long story, it turns out my CO2 burner was leaking other toxic gases in the room and poisoning my plants! I switched back to CO2 tanks and everything is running perfect now! Plus the GreenAir controller gives me about 3-4 weeks per 20lb tank instead of 1 week from the Autopilot so tanks aren't really a problem anymore.

Theres not a lot of info around about the strength of these QB's and them burning plants. If you search around, most of the threads you find on here about this will be me bringing it up. Its definitely a problem. It can be fixed though because I've done it and im crushing it with high intensity quantum boards and low ceilings now. Im sure one of my solutions or maybe a combo of them will be your solution as well. I still won't recommend quantum boards though and ill be switching to bar style LED's next time I buy lights.

 

[jimihendrix1]

yes, like I wrote

things is, why aren't young gardensprouts fried outside at 1600umol in cloudless spring days

Probably because outside theyre exposed to UVA/B from day one.

I start seedlings, veg and flower my plants under 2 Solacure 4ft Flower Power bulbs in each 4 x 4 area, and also start seedlings under a 1000w Hortilux HPS, and a Gavita 1700e. All 3 at 24 inches from canopy. I use the HPS bulbs from seedling-flowering. I use the UVA/B for 4 hours a day at 24in from seedling-flowering. I will use a longer UVA/B scheme if I use a 1150w DE Gavita DE bulb as they have to be run at 36in-40in or they will fry because of infrared.
Using a Lumen to PPF Calculator at 145,000 lumens the 1000w Hortilux puts out roughly 1881umol at 2000k The Hortilux is 2100k. Ive never had a plant burn doing this. I also have tremendous fresh air flow. My temps are between 78f-84f.

 

[Kassiopeija]

Theres not a lot of info around about the strength of these QB's and them burning plants. If you search around, most of the threads you find on here about this will be me bringing it up. Its definitely a problem. It can be fixed though because I've done it and im crushing it with high intensity quantum boards and low ceilings now. Im sure one of my solutions or maybe a combo of them will be your solution as well. I still won't recommend quantum boards though and ill be switching to bar style LED's next time I buy lights.

you make some very valid points.
what I noted from bar style racks is they typically are either just white light diode or you cant really go close up with them otherwise the rare 660nm etc supp doesnt really mix into the light recipe

that chinese manuf. solveemd that problem IMO (also his lenses to produce a controlled fraction of diffuse light is remniscient of the natural skylight outdoors)

Probably because outside theyre exposed to UVA/B from day one.

I start seedlings, veg and flower my plants under 2 Solacure 4ft Flower Power bulbs in each 4 x 4 area, and also start seedlings under a 1000w Hortilux HPS, and a Gavita 1700e. All 3 at 24 inches from canopy. I use the HPS bulbs from seedling-flowering. I use the UVA/B for 4 hours a day at 24in from seedling-flowering. I will use a longer UVA/B scheme if I use a 1150w DE Gavita DE bulb as they have to be run at 36in-40in or they will fry because of infrared.
Using a Lumen to PPF Calculator at 145,000 lumens the 1000w Hortilux puts out roughly 1881umol at 2000k The Hortilux is 2100k. Ive never had a plant burn doing this. I also have tremendous fresh air flow. My temps are between 78f-84f.

interesting report Sir. what's your light schedule? well, my take on that would be (a) initial accustomization to full spectrum + high luminosity and (b) HPS contains partially some colours (oranget, bit green) that doesnt create that much heatstress on initial tissue than blue & red (high absorption)
the HPS IR rather shines through so creates heat homogenously
though I dont wanna equate high temps with high irradiance, but certainly these things influence one another

I'm sorry I didnt quite catch that reasoning:

I will use a longer UVA/B scheme if I use a 1150w DE Gavita DE bulb as they have to be run at 36in-40in

***

that said, the plant response to UVA/B may also be helpful vs strong irradiance photodamage - it has even been shown to ve effective to alleviate some drought stress ( & vice versa)

 

[jimihendrix1]

My light schedule from seedling- veg is 24/0. Hortilux also contains some blue. Not alot, but it does have it. Ive been using the Hortilux since the 90s. Used Metal Halide before that. Since 1977-78

 

[PSUAGRO.]

True. I have no way of telling if it is LED or just not getting my recipe for the soil just right. Eventually, I'll be able to just use water and for now, I'm good with needing just one bottle for flower. I'm focusing on removing that one extra step during watering and eliminating that cost.

Efficient blurple was a pita to grow under no doubt. gg had a couple flawless runs, but he is an excellent grower. Quality " white" mid power/ cobs have proven themselves over the years in here.

You Definitely have to alter some habits coming from hid to led.

Good luck

 

[Norml56]

Efficient blurple was a pita to grow under no doubt. gg had a couple flawless runs, but he is an excellent grower. Quality " white" mid power/ cobs have proven themselves over the years in here.

You Definitely have to alter some habits coming from hid to led.

Good luck

I'm still running both HID and LED in my flower side so hopefully, I can dial the soil in sooner.

 

[PSUAGRO.]

I'm still running both HID and LED in my flower side so hopefully, I can dial the soil in sooner.

You got this grower, Los/rols makes it easier. A little cover crop don't hurt either, helps with the watering habit.

 

[Hobbes]

The 650 Diabo is a strong light with a hot spot.

I got an HLG 650 R-Spec. It is shaped like two capital Es back to back. They came out with the R-Spec a month after I bought the Diablo. I wasn't too happy. I'm using the Diablo as a veg light, turned way down. It's flowering an auto as well.

.

What is better about the R-Spec over the Diablo?

.

 

[Artmann11]

.

What is better about the R-Spec over the Diablo?

.

The diablo is a square. The boards are all together. It has a hot spot. It's very powerful, if you're not careful, to the point of plant damage.

The R-Spec is shaped like two capital Es back to back. The quantum boards are spread out and don't burn the girls nearly as much. It was built to be able to get much closer to the canopy

 

[Artmann11]

Scorpion R-Spec. Before you ask, the left side of the plant reached for the sky. Lol. It kept going even after I topped it in veg. Wall buds.

 

[catdaddy516]

The diablo is a square. The boards are all together. It has a hot spot. It's very powerful, if you're not careful, to the point of plant damage.

The R-Spec is shaped like two capital Es back to back. The quantum boards are spread out and don't burn the girls nearly as much. It was built to be able to get much closer to the canopy

Hmm. I wish i would've know this before recently purchasing the Diablo. I just had to raise it 3' over the canopy because it was frying my plants at 80%.

 

[Artmann11]

Hmm. I wish i would've know this before recently purchasing the Diablo. I just had to raise it 3' over the canopy because it was frying my plants at 80%.

I hear ya. They came out with the r-spec one month after I bought my Diablo. I was so pissed. Just left them a message. I'm no electrician but I asked how much the aluminum blank is from the R-Spec. I may switch the quantum boards over.

 

[Artmann11]

was never able to run the R-Spec at full power either. It did burn the leaves but not near as bad as Diablo. R-spec still had record harvests (for me). Much better than 2 600 watt HPS lights. But then again, so did the Diablo. It outperformed my HPS, even with the burn.

 

[OneHitDone]

I think your confused. Both the Diablo and the R-spec are available in the "Scorpion" configuration

 

[hillbill]

Iam running 4 single boards at 100 watts each in a 2 1/2 x 5 foot tent. I run perpetual and can adjust each and move each as need be. There is no penalty in performance like lower watt HPS.