12/12 From Seed LED Distance/Darkness?

Hey everyone, I was just getting into trying a 12/12 from seed setup with 8 3 Gallon pots in a 3x3 tent. I had some dumb questions if anyone with experience with 12/12 from seed could answer I would appreciate it.

I am using Mars II 700 300 Watt running without bloom spectrum on 350 with Bloom spectrum light switch on
Coco Coir - Perlite temps are good 73-78 airflow is good little wiggle to them.

I have the LED at about 30 Inches from the tops of the plant. I am getting reaching issues but don't quite know a safe range for LED yet. I had lots of drooping last time I set an LED 25 inches away from a plant during flowering. They are tall ass twigs 4 inches fucking dental floss stem now and hoping that they can recover from this and start thickening up.

How important is the dark factor on 12/12 from seed I am about 5 days in. I am not making the dark 12 completely dark just lights off for now - closing tent up a bit if any light leak its below pots around zipper. (Mainly testing temperatures and airflow).


So if anyone has any recommendations on LED distances so I don't torch the plants and that I don't have reach issues I would appreciate it very much.

I know I need completely dark about 2 to 3 weeks in i'm just not sure about right now.

Thanks.

Drop to around 20-24" to limit stretching

Budzbuddha said:

Drop to around 20-24" to limit stretching

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Alright Ill give that a go, Thank you.

You do realize that the 12/12 will trigger flowering, so you may want to increase that schedule maybe u p to 18/6 ?
Plus what I have had occur to me using LED's close to the full life of a plant is interesting growth variations.
I'd maybe feed them a little white light.....T5's are my veg light of choice, but there are tons of options.....I pop using the good ole Sun.
As far as distance....I have burnt and killed a 6 inch from seed Ghost of LeRoy from RD using a 50 watt UFO. Be careful.

meowmeowmeow said:

You do realize that the 12/12 will trigger flowering, so you may want to increase that schedule maybe u p to 18/6 ?
Plus what I have had occur to me using LED's close to the full life of a plant is interesting growth variations.
I'd maybe feed them a little white light.....T5's are my veg light of choice, but there are tons of options.....I pop using the good ole Sun.
As far as distance....I have burnt and killed a 6 inch from seed Ghost of LeRoy from RD using a 50 watt UFO. Be careful.

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Pretty sure he knows 12/12 is the flowering light cycle.

Also, I use LED the whole way through. No problem.

Lower the lights.

FIrst 2 weeks of seedling do 18/6 or 20/4, then switch to 12/12

30 inches is way too high. PAR is probably next to nil from that height.

Go, like, 18".

superbak3d said:

Lower the lights.

FIrst 2 weeks of seedling do 18/6 or 20/4, then switch to 12/12

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That's what I wanted to know. I was thinking in my mind that would be better get some nice early growth in.
Thanks.

Olive Drab Green said:

30 inches is way too high. PAR is probably next to nil from that height.

Go, like, 18".

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I was considering getting it that low but I gotta do it when I can keep an eye on them. Like I mentioned in my post last time I worked with this led 25 inches from the tops was too close or the plants didn't like it in mix with the HPS. I Tried to introduce the LED right before flowering to see how temps and setup would go and I saw the issues the next day. Ended up delaying me a little waiting for it to return to health.

Have you personally worked with LEDs? With some research I kept coming up with 2.5 feet - 3 feet from the tops of the plant. I am down to try whatever distance if I can leave them for a day and they won't take any burn or droop.

superbak3d said:

Lower the lights.

FIrst 2 weeks of seedling do 18/6 or 20/4, then switch to 12/12

Click to expand...

@Chodee - i don't know if the 12/12 thing is to prove some point or something but wouldn't it be better to test them on a regular veg cycle (24/0,20/4,18/6) in order to dial in your light distance?

I ran the old style 100x3 mars for a couple grows and their distances are fucked up big time. they say like 30" during veg and seedling and as close as 12" during flower. I ended up opening up the case by removing the glass and using an extra clip on fan to blow over the leds/heatsink so that i could run them about 6-8" away. However, after all that fucking around and trying to fight the temperatures i just ended up converting my mars led into an ass kicking cob led.

Chodee said:

I was considering getting it that low but I gotta do it when I can keep an eye on them. Like I mentioned in my post last time I worked with this led 25 inches from the tops was too close or the plants didn't like it in mix with the HPS. I Tried to introduce the LED right before flowering to see how temps and setup would go and I saw the issues the next day. Ended up delaying me a little waiting for it to return to health.

Have you personally worked with LEDs? With some research I kept coming up with 2.5 feet - 3 feet from the tops of the plant. I am down to try whatever distance if I can leave them for a day and they won't take any burn or droop.

Click to expand...

I've only ever used LEDs. Trust me. 18". How old is your plant, and what brand and wattage is your light?

SamsonsRiddle said:

@Chodee - i don't know if the 12/12 thing is to prove some point or something but wouldn't it be better to test them on a regular veg cycle (24/0,20/4,18/6) in order to dial in your light distance?

I ran the old style 100x3 mars for a couple grows and their distances are fucked up big time. they say like 30" during veg and seedling and as close as 12" during flower. I ended up opening up the case by removing the glass and using an extra clip on fan to blow over the leds/heatsink so that i could run them about 6-8" away. However, after all that fucking around and trying to fight the temperatures i just ended up converting my mars led into an ass kicking cob led.

Click to expand...

The reasoning for the 12/12 from seed is mainly just a test It's a side grow to test out a few different strains. In theory I am doing it so they stay low and I can fit 8 in the tent. I have read before of people doing it in similar ways. It's mainly so I can use these 8 different strains to test them out and grow some yielders next of my favorites. If you have any suggestions of a better method I'd appreciate it but my goal is just to grow smaller so I don't have issues with 8 plants in a 3x3.

Thanks for the information on the Mars LED also If it gets bad with temps I have plenty of fans and portable AC to take care of it. I have no clue what the hell a cob led is but if it's ass kicking i'm going to try to read into that later when I get a chance.

Thanks.

Be careful with those cobs mate. They put out a lot of green light relative to the mars LED's and I'm sure you know it won't do anything for your plants. That's the thing about cob LED's mate. You either go regular LED's or you go hps/Mh. I just don't like cobs,

Chodee said:

The reasoning for the 12/12 from seed is mainly just a test It's a side grow to test out a few different strains. In theory I am doing it so they stay low and I can fit 8 in the tent. I have read before of people doing it in similar ways. It's mainly so I can use these 8 different strains to test them out and grow some yielders next of my favorites. If you have any suggestions of a better method I'd appreciate it but my goal is just to grow smaller so I don't have issues with 8 plants in a 3x3.

Thanks for the information on the Mars LED also If it gets bad with temps I have plenty of fans and portable AC to take care of it. I have no clue what the hell a cob led is but if it's ass kicking i'm going to try to read into that later when I get a chance.

Thanks.

Click to expand...

Olive Drab Green said:

I've only ever used LEDs. Trust me. 18". How old is your plant, and what brand and wattage is your light?

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I am using Mars II 700 300 Watt running without bloom spectrum on 350 with Bloom spectrum light switch is on. The plant is like 6 days old from sprout. It's a baby I supplied pictures up above.

If you are talking about the one I originally tried it on it was about 5-6 weeks into vegetative. I was using a 600 Watt MH Bulb Brands some cheap light ad then I went to introduce the Mars light at 25 inches and was extremely noticeable my plant was bitching at me about setting that fucker on her.

Chodee said:

I am using Mars II 700 300 Watt running without bloom spectrum on 350 with Bloom spectrum light switch is on. The plant is like 6 days old from sprout. It's a baby I supplied pictures up above.

If you are talking about the one I originally tried it on it was about 5-6 weeks into vegetative. I was using a 600 Watt MH Bulb Brands some cheap light ad then I went to introduce the Mars light at 25 inches and was extremely noticeable my plant was bitching at me about setting that fucker on her.

Click to expand...

18-24".

Olive Drab Green said:

18-24".

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Yeah, I actually got time today to adjust it.

Everyone's advice leads to dropping it a bit. I'm just used to having my CFLs like 2 inches away and my HID really close also. These LEDs are a bit different.

Thanks again everyone for all the information.

what nutes do you guys feed your clone in the 1 -2 week veg before fliping it to flower

meowmeowmeow said:

You do realize that the 12/12 will trigger flowering, so you may want to increase that schedule maybe u p to 18/6 ?
Plus what I have had occur to me using LED's close to the full life of a plant is interesting growth variations.
I'd maybe feed them a little white light.....T5's are my veg light of choice, but there are tons of options.....I pop using the good ole Sun.
As far as distance....I have burnt and killed a 6 inch from seed Ghost of LeRoy from RD using a 50 watt UFO. Be careful.

Click to expand...

Even a seed straight from 12/12 will still veg for a few weeks before shooting off pistols. Just putting that out there.