The Grow Awards 2026 🏆 
Light intensity in veg - Help needed!
arg_weedloverstarted grow question 4y ago
I have a 4x4 Tent (120x120cm) with 16 Autos and run a 480W 3.5K LED at ~55 % at a dist. of 40-48 cm (1.3-1.5 feet).
Lux: 20-26k. They are tall with up to 14 cm (0.45 feet).
What would be the right light density in week 2-3?
Ideas? Plz help! THX
Solved
Setup. Lighting
likes
Autofemweedanswered grow question 4y ago
Bro en etapa vegetativa la planta necesita para su crecimiento óptimo entre 400 a 600 ppfd.
arg_weedloveranswered grow question 4y ago
everything fine now.
Luxmeter is woth nothing, with a parmeter and 600ppf all is fine...
thx ppl!
likes
Complain
Appoldro420answered grow question 4y ago
Keep it simple, just lower the lights to 35cm. 480W is not too much for the room
1 like
Complain
nerdzanswered grow question 4y ago
Buy a Lux meter man they're . I'm at day 17 and just touching them with 20k
1 like
Complain
Odin9answered grow question 4y ago
First 2, 3weeks 20to35000luxand 30 to 50000 lux in flower
1 like
Complain
Similar Grow Questions
Solved
HappyLittleAxeDents
Lamp to Plant distance - Outdoor.If growing outside, what is the best way to calculate lamp (star) to plant distance for the journal each week based on time of year and rotation of our lovely planet? I am being facetious, of course! It's just a fun question for you all. Hope everyone out there good!Setup. Lighting
Setup. Outdoor
5y ago
5
3
Solved
Frog35
LED light distanceHey guys I'm kind of new to growing only been doing it for a little over a year. My girls grow really well they just don't get very tall I'm thinking it's because my lights are too close. Is this correct? Distance is 9 inches above canopy in week 6 growing critical 2.0 autos.Week 6
Setup. Lighting
3y ago
11
7
Solved
EXZELENS
Can I change my autoflowers light cycle withou reducing their yield significantly?I am having humidity/mold problems and was thinking of changing the cycle so the grow goes off at noon ( currently it goes off at 1am and its winter and gets real cold with 88% humidity).
Even if I stress them, it would be better to not have mold than reducing the yield, right?Other. Mold
Other. General questions
Setup. Lighting
5y ago
1
1
Solved
Hou_Stone
a good lamp ?Good morning,
Currently I have an hps and I'm looking to invest in a good lamp. Do you have a good one to recommend?
I have a room 100x100x200 cm
Currently I want to take the mars hydro fc3000 I am not sure if it is powerful enough for my room? I would like to have opinionsSetup. Lighting
3y ago
4
6
Solved
SWUKGrower
Will a 1000w LED be enough for flowering?Im about to start my 3rd ever grow, now I cant get enough of it. For my last 2 grows, in a 90x90x200 tent, I've has a MARS Hydro TS 1000w LED for Veg / 600w HPS for Flowering.... Can I use only the LED throughout? The heat from the HPS is crazy. Cant wait to start posting on hereSetup. Lighting
5y ago
5
5
Solved
TonkaSun
what is correct light schedule for indoor germination and seedling, and then transplant outdoors?I plan to grow a photoperiod plant outdoors from spring to fall, but the germination and seedling stages will be done indoors. For the indoor part, can I use a setup with 18 hour light schedule? Or should it be 12 hours? I don't want to trigger flowering when I put it outside.Setup. Lighting
3y ago
1
6
Solved
rich_kraft
Light cycle after germinationIs 24 hr lights at this stage too much?? Yield is not a priorityWeek 1
Setup. Lighting
6y ago
1
1
Solved
GreenleafSWO
Grow light height in floweringI have a lumatex ATS 200w led, I've it raised to max height but I've still only 10 inches of clearance from the canopy. It's flowering now and upward growth has stopped as buds are starting to fill out, will I be ok with this short distance?Week 8
Setup. Lighting
3y ago
2
4
Solved
Goldenbags
Contemplating putting 2 plants outside. I have 8 in a 3x3 with Mars hydro tsw2000. It’s pretty tight in there. What do you guys think? Is 8 too many for the size and light? Or should I just leave them as is? I think the the pots are 3 possibly 5 gallon.Week 4
Setup. Lighting
3y ago
8
8
Solved
Mackorodoo
Possible N toxicity or damagePossible nitrogen toxicity light damage or ph issue one plant wwa is all curled up and barely growin 3 weeks in bi has yellow tips and a few small holes peyote is starting to grow oddly and blue dream seedlings are all iver the placeLeaves. Twisted
Leaves. Color - Yellow
Setup. Lighting
5y ago
2
Solved
Dazed_And_Confused
Grow Light for 3x3 tentLooking for a good grow light for a 3x3 flower tent.
-Price is not an issue
-Low heat since I am venting into my living area.
-Even light distribution. I plan on doing a SCROG so having the same light intensity on the edges as the center would be best.Setup. Lighting
5y ago
7
Solved
buddhi_coop
Grow LightsIs it okay to use an LED Light 1000 watt (4x4x80" tent) & a UV Light 1000 Watt in a 4x4x80" grow tent for 3 plants. I want more light, I have plants growing slowly so I'm hoping to adjust the amount of light I have would speed up their growth. LED is white spectrum & UV blue-vegLeaves. Tips - Burnt
Setup. Strains - Photoperiod
Setup. Lighting
5y ago
4
3
Solved
ngenius
hey guys , a have a question regarding light.
So, I have 2 autoflowers under a 130w led right now both age 14days exactly.
In a couple days a will also have the mars hydro ts600.
I am working with a 1meter squared tent.
how high sould i hang my lights during veg and flower ?Setup. Lighting
4y ago
2
4
Solved
Nurse
possible light burn help me tanxI have two lights, spider sf 1000 and viparspectra p1000. My plants have burn marks. I do not know if it is from lights or fertilizers. I now keep them 18 inches apart. Can anyone tell me the light distance table? How far should they be now?Setup. Lighting
5y ago
1
2
Solved
Cannabis_carlitos
What % to keep lights at during late vegMy question was around what power % I should have my lights at? My light is 300watts so I am assuming 50% = 150watts?
Is this enough to continue vegging my plant? I have noticed the growth isn't as vigorous.Week 11
Setup. Lighting
3y ago
2
5