Is my seedling sick? Bright green leaves

[ryanisgrowing]

Hello! I'm growing 3 autoflower gorilla glues in coco coir, its my first grow. I'm currently using a 300w LED about 18 inches above. This seedling is almost 5 days old, its the biggest of the 3 but its first leaves are and have been for a while bright green. It seems like its been getting progressively lighter each day. I just started giving them nutes yesterday and fed about 15ml/gal of rhizotonic(i may have fed too much, found out after that I shouldn't feed according to the bottle but instead at 1/2 strength or even 1/4th) and 2ml of cal-mag+.

The leaves are also a little bit flimsy looking and some of the serraded edges are starting to curl up. Wondering if anything is wrong with her? the others look alot darker and not as flimsy. The last 2 pictures ill post are of the other 2 seedlings so you can see the differences. Thanks for helping me out

 

[ryanisgrowing]

Hello! I'm growing 3 autoflower gorilla glues in coco coir, its my first grow. I'm currently using a 300w LED about 18 inches above. This seedling is almost 5 days old, its the biggest of the 3 but its first leaves are and have been for a while bright green. It seems like its been getting progressively lighter each day. I just started giving them nutes yesterday and fed about 15ml/gal of rhizotonic(i may have fed too much, found out after that I shouldn't feed according to the bottle but instead at 1/2 strength or even 1/4th) and 2ml of cal-mag+.

The leaves are also a little bit flimsy looking and some of the serraded edges are starting to curl up. Wondering if anything is wrong with her? the others look alot darker and not as flimsy. The last 2 pictures ill post are of the other 2 seedlings so you can see the differences. Thanks for helping me out

Also I forgot to mention. I've been watering and feeding using ro water 5.8-6.5 pH, about 100-250 ppm. The plants are getting plenty of air in my 2x2x4 tent. The temperature is about 75-82 f, with about 50% humidity.

 

[Simplicio]

Light green is the color of new growth.
But it can also be the color of light burn if it happens on mature leaves.
Seedlings don't tolerate light or nutes very well.
Give them too much of either, and it can kill them.
Too little only slows growth, so err on the too-little side.
24 inches distance under a COB burnt mine.

Also, your humidity is much too low according to the Vapor Pressure Deficit chart.

 

[ryanisgrowing]

Light green is the color of new growth.
But it can also be the color of light burn if it happens on mature leaves.
Seedlings don't tolerate light or nutes very well.
Give them too much of either, and it can kill them.
Too little only slows growth, so err on the too-little side.
24 inches distance under a COB burnt mine.

Also, your humidity is much too low according to the Vapor Pressure Deficit chart.

What is a COB LED? How do i know if the one i have is COB? I'm using a topolite 300w led. Its a replacement right now until my mars hydro 600w comes in a few days. I've just put a humidifier in my room near the tent and the humidity in the tent is now about 62%. Also, I wanted to ask, what ppm i should be feeding to them at this stage? Thanks for the help

 

[Simplicio]

What is a COB LED? How do i know if the one i have is COB? I'm using a topolite 300w led. Its a replacement right now until my mars hydro 600w comes in a few days. I've just put a humidifier in my room near the tent and the humidity in the tent is now about 62%. Also, I wanted to ask, what ppm i should be feeding to them at this stage? Thanks for the help

Stands for "Chips On Board."
COBs are just LEDs mounted on a self-cooling electronics board.
They tend be be a good value.

There aren't right or wrong answers to many questions, and using the average opinion is probably best.
My opinion is that your seedling should be fed 100 ppm or less for a few days, and that the lights should be moved to 30 inches away until the seedlings adapt.
This can create stretch if an oscillating fan isn't used to blow a gentle breeze, but too much wind velocity is harmful.
A fan blowing on and moving a tent panel can simulate an oscillating fan because of reflected air. There should be a very gentle swaying of the plants to thicken stalks.

Google VPD chart, and you'll get lots of hits.

 

[ryanisgrowing]

Stands for "Chips On Board."
COBs are just LEDs mounted on a self-cooling electronics board.
They tend be be a good value.

There aren't right or wrong answers to many questions, and using the average opinion is probably best.
My opinion is that your seedling should be fed 100 ppm or less for a few days, and that the lights should be moved to 30 inches away until the seedlings adapt.
This can create stretch if an oscillating fan isn't used to blow a gentle breeze, but too much wind velocity is harmful.
A fan blowing on and moving a tent panel can simulate an oscillating fan because of reflected air. There should be a very gentle swaying of the plants to thicken stalks.

Google VPD chart, and you'll get lots of hits.

Thank you! that chart make things much clearer. And yikes, I think the ppm on my last feed was close to 400 per cannas nutrient schedule, ill dial it down and probably only give 1/4th strength. I'm just worried it might be an iron deficiency thats turning the leaves light green aswell. Is it alright that the fan is blowing air + humidifier smoke straight into the tent? I've positioned the ducts to blow toward the plants so they get a very gentle swaying. Also have moved the light up to 26' which is the max i can put it up because the inline fan and carbon filter are in the way. Thinking of moving some stuff around so i can bring the lights up higher.

 

[Simplicio]

Thank you! that chart make things much clearer. And yikes, I think the ppm on my last feed was close to 400 per cannas nutrient schedule, ill dial it down and probably only give 1/4th strength. I'm just worried it might be an iron deficiency thats turning the leaves light green aswell. Is it alright that the fan is blowing air + humidifier smoke straight into the tent? I've positioned the ducts to blow toward the plants so they get a very gentle swaying. Also have moved the light up to 26' which is the max i can put it up because the inline fan and carbon filter are in the way. Thinking of moving some stuff around so i can bring the lights up higher.

The plants will look happy when they are happy, and it might take them a few days to decide, after doing something to them.
My 3 week olds are very happy on 270 ppm in a top feed hydro system right now, but they weren't happy a week ago on 300 ppm.
At that time they were also extremely unhappy with 24 inch lighting.

Now is the time to create more vertical space, so your idea is a good one.

 

[ryanisgrowing]

The plants will look happy when they are happy, and it might take them a few days to decide, after doing something to them.
My 3 week olds are very happy on 270 ppm in a top feed hydro system right now, but they weren't happy a week ago on 300 ppm.
At that time they were also extremely unhappy with 24 inch lighting.

Now is the time to create more vertical space, so your idea is a good one.

Hey Simplicio, today was a productive day I moved the inline fan outside so for now I have plenty of room. Also the mars hydro 600w just came in, I just set it up. What height would you suggest me put it at? right now I have it capped at 28' just to be safe. By the way, the sick plant is already looking better, I can see its starting to regain its darker green color. The coco is still wet from about 2 nights ago so I haven't been able to change the feed to 100~ ppm. I'll post pics when I have time tomorrow if you'd like to see them. Thanks again for all the help.

 

[Simplicio]

Hey Simplicio, today was a productive day I moved the inline fan outside so for now I have plenty of room. Also the mars hydro 600w just came in, I just set it up. What height would you suggest me put it at? right now I have it capped at 28' just to be safe. By the way, the sick plant is already looking better, I can see its starting to regain its darker green color. The coco is still wet from about 2 nights ago so I haven't been able to change the feed to 100~ ppm. I'll post pics when I have time tomorrow if you'd like to see them. Thanks again for all the help.

Light distance is like much else with growing: less can be more.
The object is to give the plants the most light they can handle, but not more.
That depends on the exact setup and exact environment.
I usually take the manufacturers' suggestions as the CLOSEST distance the plants can tolerate, and start higher.
The harm from lights too far away is less yield and potential stretch (with insufficient breeze); from too close, it's burn likely followed by less yield.

I've got some new COBs that I'm struggling to find the correct distance for also.

 

[ryanisgrowing]

Light distance is like much else with growing: less can be more.
The object is to give the plants the most light they can handle, but not more.
That depends on the exact setup and exact environment.
I usually take the manufacturers' suggestions as the CLOSEST distance the plants can tolerate, and start higher.
The harm from lights too far away is less yield and potential stretch (with insufficient breeze); from too close, it's burn likely followed by less yield.

I've got some new COBs that I'm struggling to find the correct distance for also.

It didn't come with a manufacturers booklet, I found a mars hydro diagram showing the μmol's per distance, 350 μmol's at 36', 650 at 24'. I read that 250-400 is best for seedlings, but from other growers using the same light their plants do fine at 24-30' as seedlings. Here's a couple pictures of how they're doing. The smallest one has been pretty dormant for a few days and the stem hasn't grown taller like the others.