[MrNoice]

Hi fellas, me again, annoying you guys as I am a absolute newbie, but I just keep reading conflicting articles on lighting..

I currently have 6 plants, white widows, 2 are in preflower, and 4 are seedlings, I've moved the seedlings into a smaller tent with a Spider Farmer 100w light because I had the 2 Marcs FCE3000 on 75% which seems to have caused some light burn, I've had the same issue before on this grow and just moved the light up.

But if I am running 2 x 300w for 2 plants in a 3X3 tent, what is the optimal lighting? Should I just run both at 50% all cycle? 100% on 2 lights for 2 plants seems quite a lot, even at 75% it seems a lot.

My question is how important is the 0-100% lighting ratio, MARS advise 25% for seedlings, 50% veg and 75/100 in flower, is this because of some spectrum of the lights that change like in HPS blue/red spectrum? am I good to run the lights at 50%?

Also, I've seen people growing plants that are seedlings, in veg and flower in the same tent, how does that work if each plant is in a different phase? I.E 50% may be okay for a vegging plant but for a seedling this would roast it.

Would it be better to start off the seedlings until 2 weeks in a 1X1 tent and only have mature vegging and flowering plants in the main 3x3 tent? is 2 X 300w overkill also? or for full light coverage would 50% on both lights be ideal for a 3x3 space?

Thanks once again guys!

 

[Bdubs]

You are running more lights in the space. You can no longer go by single light fixture ppfd and distance to adequately gauge your lighting.

You have to rely on lux meter, ppfd readings over manufacturer recommendations now.

More diodes or light sources alters the perceived light that you see on your lights charts.

You need to run lower intensity to achieve the same actual ppfd. Which just means that you will aim for a different light spectrum in the lights you use, because you chose to run 2 lights.

 

[T_Dub]

I think you (and most growers) would benefit from a light meter. There are different types and price points. A lux meter, while not ideal for LEDs, is a cheap option to measure the amount of light on your plants. Personally, I use the “Photone” app on my iPhone and a light diffuser sold by that app ($26) for use with my iPhone. It beats guessing, which is your current technique. I’d rather know exactly how much light my plants are getting as I progress through veg and flowering.

 

[Bdubs]

My question is how important is the 0-100% lighting ratio, MARS advise 25% for seedlings, 50% veg and 75/100 in flower, is this because of some spectrum of the lights that change like in HPS blue/red spectrum? am I good to run the lights at 50%?

100% isn’t the importance. It is the ppfd and most importantly the DLI. But light spectrum can affect how your bud grows.

 

[Bdubs]

That’s when lights and their spectrum and intensity matters when you use more than one light. If you use a single light in a 4x4 tent for example you could totally adhere to manufacturer recommendations and be pretty accurate, distance and intensity wise.
It adding more lights, you are forced to reduce intensity for the same PPFD and DLi.

 

[T_Dub]

Tdub agrees with B dubs. Haha. Sometimes a picture helps. This is the recommended daily light integral (DLI) that you should target by plant age. Just a demonstration, but it’s a measure of how many hours of light per day and light intensity (ppfd). The Photone app calculates DLI for you.

 

[Smokeshow]

@T_Dub I am curious which diffuser you bought, can you tell me the name or brand? I see several on amazon, but I was not sure which to get for use the the photone app. Thanks!

 

[Bdubs]

I am doing this stupid “muscle training” lighting on my plants. I didn’t just hop them up to 100%. I went ~45% all veg, went 60% weeeeks before flower. Then, 5% bump into flower. 15% bump at week 2. 5% bump for 80% at week 3. I’ll bump 5% every week, watching leaf stress and foxtailing as any signal I am going too far. But my goal is to fatten them shits up as much as possible on bidding phase, but once I hit week 6 I’ll start light intensity reductions5% at a time and it will assist in temps. But I will stop intensity reductions as long as canopy temps can maintain 75degrees high during lights on. I want my size, but then I want to tighten everything up for a moderate density bud.

 

[Bdubs]

But the light reductions of intensity helps temps. You can use night time hours to enhance terpenes and reduce DLI!

 

[T_Dub]

@T_Dub I am curious which diffuser you bought, can you tell me the name or brand? I see several on amazon, but I was not sure which to get for use the the photone app. Thanks!

This is only for the Photone app….

Diffuser & Cosine Corrector | Lightray

The Lightray clip-on Diffuser & Cosine Corrector accessory enables to measure light with any smartphone camera.

lightray.io

 

[Newty]

The lighting guide that manufacturers give with grow lights are usually very over powered.

I run 3 tents.
8x4 has 1400 watts, 2 Vivosun VS4000 and a HLG Scorpion RSpec 600

4x2 has Spider Farmer SE4500 430 watt

3x2 has AC Infinity Ionframe Evo3 280 watt

What I'm getting at is they're all different manufacturers but I run them all exactly the same.

Veg - 30%-40% intensity 30" over canopy, everytime they grow to around 24", I move it back up to 30"

Flower - stay at 30%-40% for 2 weeks, increase 10% on week 3, increase 10%-20% each week after.
Once I'm in the higher intensity range and in the middle of flower, I let it ride for a few weeks and then slowly start decreasing intensity each week toward the end of the flower cycle.

Height during flower is around 24", if they stretch to much and I run out of height and end up closer then 24", I lower intensity to counteract.

My lights usually don't run over 80%, sometimes lower depending on what the plant is telling me.

Also it's good to note that the higher the light in the tent, the more area it will cover.

Here's a good article on cycling intensity in flower like I mentioned above.

Cycle the Intensity of Grow Lights for better Plant Response

oklahoma-cannabis-company.com

 

[Smokeshow]

That is great info @Newty Thanks for sharing!

 

[BigF]

Don't chase percent dimming, measure the light, or you will always be guessing and trying to chase down conflicting advice. Use Photone on your phone or spend 30 bucks for a lux meter on Amazon. Can't stress enough the importance of measuring and testing.

 

[Captspaulding]

Hey man, can I see a picture of the plant? I just want to take a look at what you got going on

 

[Captspaulding]

Don't chase percent dimming, measure the light, or you will always be guessing and trying to chase down conflicting advice. Use Photone on your phone or spend 30 bucks for a lux meter on Amazon. Can't stress enough the importance of measuring and testing.

Yeah, but you don’t need a light meter to tell whether or not your plant is being stressed by either the light proximity or the lights output that’s not gonna change anything because basically all strains are different subjective to the light so it’s constantly gonna be a game of you know, turning your light down or adjusting its height in order to maximize the growth potential of your plant just because One cultivar could finish out at 70% output. And another at 90% Doesn’t mean that it’s yield is going to suffer if that’s what makes your plant the most happy. you catch my drift. You don’t have to go that route with every strain. So basically my point is is if you have 70% output and your plant is happy all throughout every stage of growth all the way to harvest that’s gonna have bigger healthier buds on it than a plant that’s been stressed 90%

With a lot of strains man less is more you know and there’s no lux meter in the world that’s telling you whether or not your plants are getting fucked off due to light stress,
Every strain is different under these lights, man. There’s no cookie cutter approach with a luxe meter that’s going to change that train your eye.

Also, if you set your light Really high with a low output at the beginning of every stage of growth all you gotta do is just dial it down to your plants You just gotta know what to look for damage wise on your leaves and do diligent The telltale signs of these things don’t very from strain to strain

 

[amneziaHaze]

300w is enough for a 3x3

Quick Guide – Lux Levels for Optimal Cannabis Growth

Life StageMaximumGoodMinimumVegetative70,000 lux40,000 lux15,000 luxFlowering85,000 lux60,000 lux35,000 lux

< 15,000 lux – sparse or “stretchy” growth – plant isn’t getting enough light
15,000 – 50,000 lux – a good amount of light for healthy vegetative growth
45,000 – 70,000 lux – the optimal amount of light for cannabis plants in the flowering (budding) stage. If grow lights produce a lot of UV light (such as LEC), stay on the lower side of this range
70,000 – 85,000 lux – a lot of light, some strains thrive at this light level, but some plants (especially auto-flowering and Indica strains) lose their top leaves early under this light intensity. At these levels, lights need to be kept further away for healthy growth
> 85,000 lux – at this light intensity, you’ve hit the plant’s “saturation point” which means your plant can’t use all the light (most strains will experience light bleaching or other major signs of stress at this level!)

 

[BigF]

Yeah, but you don’t need a light meter to tell whether or not your plant is being stressed by either the light proximity or the lights output that’s not gonna change anything because basically all strains are different subjective to the light so it’s constantly gonna be a game of you know, turning your light down or adjusting its height in order to maximize the growth potential of your plant just because One cultivar could finish out at 70% output. And another at 90% Doesn’t mean that it’s yield is going to suffer if that’s what makes your plant the most happy. you catch my drift. You don’t have to go that route with every strain. So basically my point is is if you have 70% output and your plant is happy all throughout every stage of growth all the way to harvest that’s gonna have bigger healthier buds on it than a plant that’s been stressed 90%

With a lot of strains man less is more you know and there’s no lux meter in the world that’s telling you whether or not your plants are getting fucked off due to light stress,
Every strain is different under these lights, man. There’s no cookie cutter approach with a luxe meter that’s going to change that train your eye.

Also, if you set your light Really high with a low output at the beginning of every stage of growth all you gotta do is just dial it down to your plants You just gotta know what to look for damage wise on your leaves and do diligent The telltale signs of these things don’t very from strain to strain

Couldn't disagree more. Knowing less is rarely better than knowing more. Measure it, observe the plants, and you will start to notice things; this girl gets funky above 60k lux in flower, while that one goes ham at 110k.

I said nothing about any cookie cutter approach.

Here is a little of what I am working with. Noticed you are on staff here. Anti science is a bad look man. Telling people not to measure stuff is inexcusable.