is this light burn ?

Darknes01 said:

im using the lucas formula (8ml micro / 16ml bloom `flora series) and im supposed to to give this dose from start till end. currently my ppm is sitting at 920( on a 500 scale) = ec 1.84 but my plants look healthy and no sign of overfeeding,or i should say how would i now if they are being over feed ?

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I really need to start using EC, i use 700 so that seems even stranger to me.
Tbh, i dont really want to give you advice either way here lol. From what I know and have seen that seems like its way too much but its a specialized method that someone, who knows a lot more about that product than I do, put a lot of time and work into. The plant in the 2nd pic you posted looks kinda dark to me though.
Thats an interesting method, and reading a bit about it now.

If theyre overfed, the first thing that most ppl notice is slow growth.
From there watch for the more obvious signs somethings wrong like yellow and brown leaf spots or tips, plants being super dark green, tips curling under. leaves will have a different texture sometimes. Theyll get a leathery or plastic-like feel instead of feeling fresh and crisp is the best way I can describe it.

I can actually kinda show you in 2 of my own plants.
First one is a healthy and very rapidly growing young lady in my veg tent. Close attention to what it wanted the whole veg. Now that they're getting big, they've started to show signs of wanting some mag within the last week.
Second one is one of my mothers that's just kinda off in a corner. I just throw some nutes in the box and ph it now and then. This last water change I put a bit too much in but was lazy and left it.
They are the same strain but much much darker. The leaves feel thick and plastic like like they're fake.

Darknes01 said:

im using the lucas formula (8ml micro / 16ml bloom `flora series) and im supposed to to give this dose from start till end. currently my ppm is sitting at 920( on a 500 scale) = ec 1.84 but my plants look healthy and no sign of overfeeding,or i should say how would i now if they are being over feed ?

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i used to use Lucas too but i never could get above 5/10 micro/bloom without burning them. it's really just the 1:2 ratio that is important. but if can run at the full dose 8/16, do it. no need to go higher either.

rkymtnman said:

looks more like the start of a Mg deficiency to me, not light burn.

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Hi there. Was wondering if you can help me out with an issue and give me your input. I’m running gavita 1700 e leds for the first time and have issues with my plants in veg. The lights are 3 feet above canopy and dimmed down to 60% and all plants look light green with yellowish tops, purple stems and leaf edges folding up

Nugs_gallore said:

Hi there. Was wondering if you can help me out with an issue and give me your input. I’m running gavita 1700 e leds for the first time and have issues with my plants in veg. The lights are 3 feet above canopy and dimmed down to 60% and all plants look light green with yellowish tops, purple stems and leaf edges folding up

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what are you growing in? coco or soil?

rkymtnman said:

what are you growing in? coco or soil?

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Coco with 2ml calmag and 4ml floranova per gallon of r/o water with ph at 5.8
The runoff is coming out low at 5.4-5.5 on most plants. I’ve tried a heavy flush with half strength nutrients and the ph stays the same

Nugs_gallore said:

Coco with 2ml calmag and 4ml floranova per gallon of r/o water with ph at 5.8
The runoff is coming out low at 5.4-5.5 on most plants. I’ve tried a heavy flush with half strength nutrients and the ph stays the same

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what is your feed EC? runoff seems good.

maybe try 1 cal/mg and 2 fnova and feed twice a day. with about 20% runoff

rkymtnman said:

what is your feed EC? runoff seems good.

maybe try 1 cal/mg and 2 fnova and feed twice a day. with about 20% runoff

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Ec is 1.2, 600 ppm and run off ppm comes out lower at 490 ppm.

Nugs_gallore said:

Ec is 1.2, 600 ppm and run off ppm comes out lower at 490 ppm.

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seems like you are doing everything right. but the leaves look pretty bad. i don't grow in coco so i'm probably not the best to give advice. maybe start a thread in plant problems?

Ever figure out what this issue was?

Pretty sure lights are too intense. People underestimate LED's because of their lower wattage ouput, but damn are they intense!!!

Nugs_gallore said:

Hi there. Was wondering if you can help me out with an issue and give me your input. I’m running gavita 1700 e leds for the first time and have issues with my plants in veg. The lights are 3 feet above canopy and dimmed down to 60% and all plants look light green with yellowish tops, purple stems and leaf edges folding up

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Same issue, as the OP. Lights are too intense, I don't think you have the right humidity for the current light intensity, plants are shriveling up!

Darknes01 said:

So i am experimenting with my LED lights and i think i might of given my plants a little light burn.
I am using fluence spydr 2p with dimmer.
initially it was about 20" from the top of the plants and dimmed down to 30% which was using about 213 watts each light ( i have 2 of them in a 4x8 tent )
Decided to increase the lights to 40% and this is what happened( see pics ) on a few of the clones. They have been in my RDWC for 12 days.
I did a ton of research and i came up with light burn since its only at the tops but wanted to check in with you guys and get your opinion as well.
my concern is that they are not eating too much( almost nothing ) but they are growing. so im thinking the ppm/ec not dropping fast is due to them being so small that the amount that they are eating is negligible?
anyway appreciate any and all comments.
cheers View attachment 4460944View attachment 4460945

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That isn't light burn, it’s a deficiency. I would check my PH first. Yours is telling you that it’s not getting something that it needs. That could be because of what it needs is not present, or it’s there but the plant can do anything with it because PH is party poopin.

ElxFeezy said:

That isn't light burn, it’s a deficiency.

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how can you tell?

(really old post)
I'm pretty sure it's because of low temp in the room... using led, you really have to climb the temp to around 83-84F, else it looks like deficiencies...

Have2 said:

(really old post)
I'm pretty sure it's because of low temp in the room... using led, you really have to climb the temp to around 83-84F, else it looks like deficiencies...

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Why would ambient temp need to be higher when growing under LEDs?

thecannacove said:

Why would ambient temp need to be higher when growing under LEDs?

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less infrared than HID, which heats plants in a specific way where plant leaves retain the heat. An HPS room at 80f would have plants that are 80f (or more) and an LED room at 80f would have plants at about 75-77f. although most new LEDs have added extra these days. I often wonder if thats a statement from the blurple days that never died but i dont know enough about light spectrums to confirm.

madvillian420 said:

less infrared than HID, which heats plants in a specific way where plant leaves retain the heat. An HPS room at 80f would have plants that are 80f (or more) and an LED room at 80f would have plants at about 75-77f. although most new LEDs have added extra these days. I often wonder if thats a statement from the blurple days that never died but i dont know enough about light spectrums to confirm.

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Exactly!

I switched from CMH to leds in the grow tent... But I have a fan that blows 24/24 to keep it odor free (negative pressure)... And plants went south from there... As soon as I bring back the cmh, everything was back on track... So if you grow using led, raise your room temp a bit, to get the leaves in the 75-78F range.

I dont run hydro but I have had light burns on 3 different grows. Normally itll start out with top growth getting white tips then move to leaf edges then plants will droop and start fading could show nitrogen deficiency could show multiple deficiencies or just burns starting from top down. I'd go with advise given just ahead up on what to look for this is early signs of light burn. The second is the same plant about a month maybe more later. The third is another plant that was worse but made harvest. Tried running a ROI-e720 in a 4x4 as mentioned 3 times using different methods. In the last pic if you zoom in on the middle bud you can see the leaves starting to droop and are burned. Shoulda took more pics during this process but man it got ugly.

GroBud said:

I dont run hydro but I have had light burns on 3 different grows. Normally itll start out with top growth getting white tips then move to leaf edges then plants will droop and start fading could show nitrogen deficiency could show multiple deficiencies or just burns starting from top down. I'd go with advise given just ahead up on what to look for this is early signs of light burn. The second is the same plant about a month maybe more later. The third is another plant that was worse but made harvest. Tried running a ROI-e720 in a 4x4 as mentioned 3 times using different methods. In the last pic if you zoom in on the middle bud you can see the leaves starting to droop and are burned. Shoulda took more pics during this process but man it got ugly.

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looks more like nute burn to me.

rkymtnman said:

looks more like nute burn to me.

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It's not everything was good until I put the light at 720. I only use organic amendment normally less than max amount. kinda hard to burn. All three grows were fine until light was increased to 720