Moving from HPS to LED Bars, what's your experience?

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Trash_2002

Trash_2002

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Curious to see what experienced LED's growers think about it in Flowering stage:


Witch media do you use ?

How Much is your watering frequency ?

What's your Canopy Temperature/Humidity Range ?

What's your max Canopy PPFD ?

What's your VPD target ?

What's your EC Range ?

Do they Drink/Transpire more or less under LEDs ?

Do you feed more or less EC with LEDS ?

cheers!!!
 
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Trash_2002

Trash_2002

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Witch media do you use ?
Peat/Perlite 50/50

How Much is your watering frequency ?
2x/Week

What's your Canopy Temperature/Humidity Range ?
24-26.5c/RH 50-60% with lights on

What's your max Canopy PPFD ?
Still on first week but at 650ppfd, plan to slowly go to 900ppfd at the end of week 4 flowering

What's your VPD target ?
0.9-1.2 kpa for the first 4 weeks

What's your EC Range ?
1650-2000uS trought the flowering development

Do they Drink/Transpire more or less under LEDs ?
it seems they drink less/transpire less so far ime

Do you feed more or less EC with LEDS ?
I'm starting to think they need less EC than HPS, maybe i'm wrong, first time flowering with it.
 
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Harpua88

Harpua88

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Good questions. I can't comment because this is my first grow with LEDs but we'll see what a bunch of answers are......
 
Trash_2002

Trash_2002

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Yep btw you don't need to answer some or any questions, if you wish just throw in some valuable info with your experiences with theses lights.

Thanks in advance for taking the time to do this tho
 
B

BudgetGrower

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Well I built my own LED lights and done a side by side, HPS vs leds, the leds give off no heat compared to the HPS, and HPS used 30% more electric, the crop size and bud quality was the same, the hps caused a little more stretch vs the led.

You can reduce the size of rvk fan and filter with a led vs HPS(less heat to remove) and the saving on electric is really good.

There is still a lot of crap leds on the market so do your homework and by a good quality one, even the right budget ones are good "viparspectra p600"
there £69 each on amazon, 4 of them spaced out even would smash a 4ft x 4ft flower room with a 18" floor fan hung in the center, 12" above the canopy.






 
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GanjaJen

GanjaJen

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I've been using HPS/HID combo for many, many moons. Figured I'd give LEDs a shot 3 years ago and I'm still growing with them BUT I also have a tent w/ my trusty HPS. I grow organically and I have Spider Farmer LEDs.
Pros: Temps are way cooler in the tent. They also save electricity but the gap has been narrowed down alot by digital ballasts.
Cons: PAR is whacked. (I have an Apogee meter so the PAR measurements are accurate.) If you move the meter about an inch or 2 away from the center of the light, the par drops dramatically. (More than the advertised graphs they give you.) Be sure to buy enough lights for your tent or buy a light that covers the entire tent.
Yield/Plant Growth: While I have not done a side-by-side comparison, I have ran the same strains through both types of lights. My experience is the yields are about the same, nothing to write home to Mama about. Plant size was larger with HPS/HID. The biggest difference is in the bud though. HPS/HID are more flavorful and smooth. I haven't done a lab test on the potency, so that remains a matter of opinion really. To me, there was not a noticeable difference. Tons of trichomes on both, I didn't see a difference there.
There have been lab studies done on the differences between the two, so that might be a good place to start looking. My advice is to be wary of the LEDs you buy though. Do your homework and make sure they will fit your application. Also remember when you take PAR readings, get in the tent and close the door when you take your readings. The readings are more accurate than with the door being open, you lose a lot of light.
 
N

Natep

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I use a luxx 645 led pro. In a 5x5 tent with a 4x4x18 bed with living soil. It is the easiest grow I’ve ever done.
 
Ponky

Ponky

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You see your plants. Looking yellow. You dim the light. But you might need to increase nutrients and increase the light in reality. Since the seem to be able to eat more.
 
Trash_2002

Trash_2002

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Shameless Bump 😁

My initial experience with 645w flexstar bars is, start with lights at 450-500ppfd max for flowering and let em slowly, i mean sloooowwwly, go towards 750ppfd the end of week 3 and towards 900ppfd by end of week 4 to prevent light burn :-)

in my case this means lights at 60%@~1.2m from the canopy at start of flower.
Let them grow towards the lights raising the ppfd naturally when they finish week 4 flowering around 50-60cm from the lights push light to 80%.
 
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B

BillyBanchan

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While I'm too new in my comeback to be of any help here, I will say that I was not expecting modern LEDs to be so stout. I struggled with too much light early on.

Another bump for you...
 
SchwiftyGrower

SchwiftyGrower

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Light Spectrum: LEDs emit a different light spectrum compared to HPS lights. While HPS lights provide a broad spectrum with a strong emphasis on yellow and red wavelengths, LEDs can be customized to deliver specific spectra tailored for plant growth. Ensure that the LED lights you choose provide a suitable spectrum for cannabis cultivation.

Heat Management: LEDs generate significantly less heat than HPS lights. While this is generally beneficial, it’s essential to consider that cannabis plants may have adapted to the warmth generated by HPS lights. Pay attention to the temperature in your grow space, as the reduced heat output of LEDs might necessitate adjustments to environmental controls and plant spacing.

Light Intensity and Distribution: LEDs often provide more focused light and can be positioned closer to the plants. However, it’s crucial to understand the intensity and distribution patterns of your LED lights. Ensure they cover the entire canopy evenly and adjust the distance and positioning based on the light requirements of cannabis at different growth stages.


Witch media do you use ?
Soil

How Much is your watering frequency ?
Once a week in 3 gallon pots
Twice a week by the time they’re in flowering

What's your Canopy Temperature/Humidity Range ?
Week 1-4 79 canopy 81 tent. Humidity is 68
Week 4-9 temps 64-70 canopy. Humdity is between 54-62

What's your max Canopy PPFD ?
Don’t have a meter

What's your VPD target ?
Week 1-4 .9-1.2
Week 5-9 1.2-1.4
What's your EC Range ?
Don’t take readings, just following feeding schedule at half feedings

Do they Drink/Transpire more or less under LEDs ?
Always think this depends on environment, genetics, root development and airflow.

Do you feed more or less EC with LEDS ?
Same amount
 
B

BillyBanchan

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Which media do you use ?
Coco/Perlite 60/40

How Much is your watering frequency ?
1x/day (ebb&flow in veg ATM)

What's your Canopy Temperature/Humidity Range ?
75-78°/RH 52-58% with lights on

What's your max Canopy PPFD ?
Just upped to 475-525 μmol/m2s - specs say 1425 in the center at 100% and 12 inches.

What's your VPD target ?
1.0

What's your EC Range ?
1.1-1.4 during veg

Do they Drink/Transpire more or less under LEDs ?
Cannot quantify... last grow was 1996 (with HPS)

Do you feed more or less EC with LEDS ?
Cannot quantify...
 
HerbalEdu

HerbalEdu

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A friend a me both switched from a 250W hps to a spiderfarmer SF2000 200W nearly a year ago because our temperature were too hot in autumn, spring and winter and plants often burn in summer.

our observations:

we need to veg longer with LED than with the HPS
plants are shorter with the LED than with the HPS
Trunk are thinner with the HPS than with the LED
growing in SOG main colas are usually shorter and less impressive with the LED than with the HPS, on the other hand more secondary branches made it to canopy level with the LED than with the HPS.
Overall there is almost no larfy buds bottom of canopy with the LED while there is a tendencies for more larfy bud bottom of the canopy with the hps
finnaly yield dispersion depending strains and phenotypes seem roughly the same with LED than with the HPS gr/m² is roughly the same, LED offer better gr/w value than with the HPS

in the end both my friend and me are happy with the LED in comparison to the HPS, really improved our issues with heat

Wich media do you use ?

biobizz all mix

How Much is your watering frequency ?

every 7-6 days the first 3 to 4 weeks then every 3-6 days depending strains, seasons, and sometime phenotypes
we usually wait for the bottom leaves to drop a little on most phenotypes to water again

What's your Canopy Temperature/Humidity Range ?

we have no control over temperature and humidity and have to deal with what's the weather like and ambient home temperature and humidity.

temperature vary from 22°C to 36°C (may be even worse when some summer heat spike happen) depending the seasons, my temperature is almost all year long too hot while my friend experience cooler temperature
humidity in the room vary from 20% to 70% depending the seasons and the weather most of the time being between 30% 50%
in the tent humidity could be higher especially when in flower and at night.

What's your max Canopy PPFD ?

mesurement i made were coherent with what spiderfarmer say on their store page with different lamp height.

What's your VPD target ?

as said no control and from my experience plant don't seem to show signifiant difference regarding that at different growth stage

What's your EC Range ?

not measuring ec

Do they Drink/Transpire more or less under LEDs ?

they doesn't seem, has more to do with strain and phenotypes

Do you feed more or less EC with LEDS ?

Both my friend and me didn't change our feeding schedules and most strains doesn't seem to bother. Also while we run the same soil we don't use the same nutrient line , i m working with biobizz, and she's working with bio canna and biotabs - bio pk
 
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JKash

JKash

Can you out GRAV The Gravmaster???
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I actually started a side by side comparison with 1000w hps/mh to 640w phlizon.... if they were not Autos inwould have gone the full cycle... but I hate autos and kill em!

From what I saw.... anything under an mh/hps stretching was more common factor compared to LED...

As far as watering and feeding... I would say I was watering a Little more in beginning... hotter temps made it dry up quicker....

(Non comparison grow) But once in flower I was feeding 2 gallon h2o in 7 gallon pots every other day under LEDs...

I 100% will say make the switch to LED... less heat less watering due to heat... less stretching cause led light is more "constant"...
 
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