Light Distance Questions 4 week old plant

LakerGang89 · Aug 19, 2021

Hi guys. I have a question about light distance. I have a Mars hydro FCE 3000 in a 3x3. I’m wondering is this a good light distance? I feel like my girl isn’t growing to her true potential with the light this close. The light is at 75 percent power. I’ve seen people hang their light damn near to the ceiling of the tent on full blast and grow away with their plants being huge. I know I’m growing pure Indica strains so mines will be shorty and bushy. I just wanted to see if she’s the height she should be at this stage.

DankNugz420 · Aug 19, 2021

I'd say around 18 inches away from tops would be a good starting point, allot of led companies recommend 18 to 24 inches away in veg. It does look like it's got light stress judging by them drooping and looking pillowy

LakerGang89 · Aug 19, 2021

DankNugz420 said:
I'd say around 18 inches away from tops would be a good starting point, allot of led companies recommend 18 to 24 inches away in veg. It does look like it's got light stress judging by them drooping and looking pillowy

Should I turn the light up to to 100 percent

LakerGang89 · Aug 19, 2021

DankNugz420 said:
I'd say around 18 inches away from tops would be a good starting point, allot of led companies recommend 18 to 24 inches away in veg. It does look like it's got light stress judging by them drooping and looking pillowy

I wanted to keep the lux around 20-30K in Veg

2Bad · Aug 19, 2021

Theyll tell you how they feel my fce4800 (480 watt) in a 4x4 is 36inches away . i'm slowly working up the wattage i'm at 20 percent. ive had them light stressed twice in the last 2 months of veg. so i've had to lower the watts and raise it back up. I personally don't like mine to be droopy with purple stems but it might be just me. They don't need much light in veg it seems.

2Bad · Aug 19, 2021

Though I am in coco so it might be different then your situation

ImpulsiveGrower · Aug 19, 2021

I have the same light it’s very powerful. Get it like 24 inches away and have it dimmed to like 75%. There’s no way that plant is doing ok with light blasting it like that. Raise it immediately

indoorsjungle · Aug 19, 2021

LakerGang89 said:
View attachment 1158966
Hi guys. I have a question about light distance. I have a Mars hydro FCE 3000 in a 3x3. I’m wondering is this a good light distance? I feel like my girl isn’t growing to her true potential with the light this close. The light is at 75 percent power. I’ve seen people hang their light damn near to the ceiling of the tent on full blast and grow away with their plants being huge. I know I’m growing pure Indica strains so mines will be shorty and bushy. I just wanted to see if she’s the height she should be at this stage.

im a newbie to this, im using a max bloom 600w i think i had mine to close using the old distance rule used by bulb lights, i lifted my light 100mm to 430mm above highest plant and noticed a responses in growth, i do wonder if led do work better further away, and if used close dim the spectrum, i set mine up by the light casting so theres less shadow. from memory i started at 12" (300mm) im now at about 500mm.

ComfortablyNumb · Aug 19, 2021

60% - 80% in veg at 18-20 inches.
Be ready to move them higher.

Mugwort · Aug 19, 2021

LakerGang89 said:
Should I turn the light up to to 100 percent

Move it to 22” and 100% brightness and let plant appearance be your guide. Refer to PPFD map that should be in your manual. See what the value is at dead center of map. I agree with DankNugz that your plant appears light stressed. Leaves look “bleached”. You didn’t say how close your light is to canopy but judging by pic it looks < 12”. Dank said 18” and that’s probably safe but until I found out for sure I’d add a few more inches!

LakerGang89 · Aug 19, 2021

Mugwort said:
Move it to 22” and 100% brightness and let plant appearance be your guide. Refer to PPFD map that should be in your manual. See what the value is at dead center of map. I agree with DankNugz that your plant appears light stressed. Leaves look “bleached”. You didn’t say how close your light is to canopy but judging by pic it looks < 12”. Dank said 18” and that’s probably safe but until I found out for sure I’d add a few more inches!

My light was fuckin 4 inches away from the plant. It grew into the light. I have it at 18-19 now inches now

Mugwort · Aug 19, 2021

LakerGang89 said:
My light was fuckin 4 inches away from the plant. It grew into the light. I have it at 18-19 now inches now

You’re lucky they didn’t spontaneously burst into flames. Just jokin! I don’t know what others here monitoring this thread might think but I would seriously contemplate keeping that plant. Depending on how much time, 4” from your canopy...I’d be really worried it would herm or some other process within the plant vital to its quality be compromised. I’m having light issues too and it seems like getting a definitive and quantitative answer to a lighting issue should be a pretty straight forward query. I’d like to learn at least a general rule of thumb as to how the addition a second identical led light does to canopy PPFD values. Good luck!

ImpulsiveGrower · Aug 19, 2021

Mugwort said:
You’re lucky they didn’t spontaneously burst into flames. Just jokin! I don’t know what others here monitoring this thread might think but I would seriously contemplate keeping that plant. Depending on how much time, 4” from your canopy...I’d be really worried it would herm or some other process within the plant vital to its quality be compromised. I’m having light issues too and it seems like getting a definitive and quantitative answer to a lighting issue should be a pretty straight forward query. I’d like to learn at least a general rule of thumb as to how the addition a second identical led light does to canopy PPFD values. Good luck!

On the MIGRO YouTube channel he tests all kinds of grow lights and has a video that explains how to use a cheap Amazon lux meter to get ppfd values. He did all the work using 4 different models with links to all 4. I got the one that was the closest and easiest to convert but you take your lux reading from the particular device tested and multiply that by a given value that he worked out already to get great accurate ppfd readings.

Mugwort · Aug 19, 2021

ImpulsiveGrower said:
On the MIGRO YouTube channel he tests all kinds of grow lights and has a video that explains how to use a cheap Amazon lux meter to get ppfd values. He did all the work using 4 different models with links to all 4. I got the one that was the closest and easiest to convert but you take your lux reading from the particular device tested and multiply that by a given value that he worked out already to get great accurate ppfd readings.

You saw this and the guy backed it up with a quality meter and the cheap Amazon meter came close when converting lux to PPFD?

ImpulsiveGrower · Aug 19, 2021

Mugwort said:
You saw this and the guy backed it up with a quality meter and the cheap Amazon meter came close when converting lux to PPFD?

Yes and here’s the video!
He tests 4 different lux meters and gives you the equation for each. Works great I’m telling ya! He uses a 500! Apogee or however you spell it so it’s legit.

Light Distance Questions 4 week old plant

Light Distance Questions 4 week old plant

LakerGang89

DankNugz420

LakerGang89

LakerGang89

2Bad

2Bad

ImpulsiveGrower

indoorsjungle

ComfortablyNumb

Mugwort

LakerGang89

Mugwort

ImpulsiveGrower

Mugwort

ImpulsiveGrower

Privacy & Transparency

Privacy & Transparency