Help! Dude deficiency/problem!

[Mcalata]

Hello everyone, I have 25 plants under a 600w diy led light. Some white widow and some sour diesel. They are being grown in coco/perlite 90/10 in 1.3 gallon plastic pots. And being fed with grotek nutes. They were thriving in veg under a 180w led light.

Since this girls are going to be flowered in a SoG style, 4x4 tent I defoliated the lower part and fed them their last veg nutes.

But as the light turned on the area in between the leaf veins turned brown in less than 24 hours. I haven't been able to find pest and I spray them with a Neem/potassium soap/ cinnamon mix once in a while.

Could it be the stress from higher intensity light (I'm running the 600w led dimmed) and the defoliation causing this?

Any help is appreciated! Happy growing.

 

[Mcalata]

Welp I f'ed up the post title lol
anyways I should add i just switched them to 12/12 and they were 24/0 in veg

 

[Subu]

Looks like light bleach to me and I've experienced it myself recently with LEDs. Not sure about the rusty look on some leaves but that might just be the remains of light bleach after you added more Nitrogen back in..

Ultimately you need to experiment but in my limited experience:

- You can run LEDs at 40cm distance if very dimmed (like 10-35% power) for young plants. Probably more like 10-20% with your 600 watt light.
- Otherwise, you're generally going to want to have them around 60-70cm above the plants if your lights are anywhere near as powerful as my 2.7umol LEDs are. My plants couldn't handle 450w of LED at 70cm without bleaching until about week 4 of flower (4 week veg)... So your 600 is likely to be WAY overkill at the moment even to what you've dimmed it.

If I were you I'd move immediately to 70cm light height, consider dimming if above about 40-50% light and see how they respond

 

[HempKat]

I agree with the above post, when I looked at the pictures I thought it was light bleaching too although it does look a little odd to me because of the rusty look. I have zero experience with LEDs but from reading other people's posts I've come to understand that you want to keep LED's further from the plant then typical with other types of high intensity lights. I can see where a lot of people might make this same mistake if they switch from MH and HPS HIDs to LED's with HIDs it tends to be more about the heat even though it's really the intensity. What I mean is once you get them far enough away where it doesn't feel too hot (usually around 24 inches) that's far enough to protect from the intensity. With LED's being low heat I can see where people would assume they can put them closer then HIDs but it ends up being too intense even though it's not too hot.

 

[troutman]

Raise the lights.

 

[mikeross]

For sure thats light stress... either raise the lights or turn them down. At that stage you will start seeing a noticeable improvement in about 48 hours.

 

[f-e]

I don't know what 600 dimmed is. Anything from nothing to 599. A plug in power monitor would be useful, so you could see what power the light is taking. So when you get it right, it's repeatable and also info you can share. It's just a 10$ item, and can be kept simple https://www.aliexpress.com/item/Dig...ric-Wattmeter-Energy-Monitor/32959765493.html

You had 180w over 16 foot, just ~11w a foot. At that power level, you could get away with anything. I presume you are now using more power. Highlighting issues not seen before. If you had the power plug above, you could match that 180w then slowly increase. It's possible the plants grew with these low light expectations, so simply tripling demand with 500w left the tissue carrying the wrong building blocks. Like when we step off a plane and it hits us. We get used to it, but the instant heat can be fierce.

I'm without the clues I need. I see light green tops often associated calcium deficiency at switch. Standard stuff. The lines look like pH troubles, but I think it's more about the big jump in light that highlights they carried an inappropriate set of reserves. They just fell apart.


Raising the lights is just another way of turning them down. I can root, grow and flower with plants touching them. There is no logic behind raising lights beyond dimming them or spreading them better. The need to spread them is a bit of a non starter though. It's not a single HID or a laser beam that won't spread unless mounted in orbit. Though using a lens over them can be a problem. Which DIY builders sometimes do, as more parts seems a better idea. Some LEDs have a 5 degree beam angle, which is unsuitable without a lens to spread it though. DIY can be a route to mistakes.

You could turn them back down to 180w again, but the best yields are being seen with the full 600w

I just don't think they were ready, but without the numbers, I can't say. You should buy a light meter to. A known one, so you can convert to ppdf accurately. It's more use than the power meter, but together they are a nice set. The power meter is useful for incremental increases, but the light meter can do that job, with little more work. Often, having both will enable you to converse with more people. Though obviously it's all about illumination levels, so you that's not part of the conversation, something is missing.

 

[Creeperpark]

Super setup Mcalata! When I add or use high-wattage LEDs I bump up the cal-mag. The cal-mag protects the leaf tissue by strengthening the cell walls.

 

[Mcalata]

Looks like light bleach to me and I've experienced it myself recently with LEDs. Not sure about the rusty look on some leaves but that might just be the remains of light bleach after you added more Nitrogen back in..

Ultimately you need to experiment but in my limited experience:

- You can run LEDs at 40cm distance if very dimmed (like 10-35% power) for young plants. Probably more like 10-20% with your 600 watt light.
- Otherwise, you're generally going to want to have them around 60-70cm above the plants if your lights are anywhere near as powerful as my 2.7umol LEDs are. My plants couldn't handle 450w of LED at 70cm without bleaching until about week 4 of flower (4 week veg)... So your 600 is likely to be WAY overkill at the moment even to what you've dimmed it.

If I were you I'd move immediately to 70cm light height, consider dimming if above about 40-50% light and see how they respond

Welp it seems everyone agrees on the problem being light stress, I might have left the dimmer set too high. I have alredy dimmed the light and se what happens in 24/48 hours.

Thanks to everyone that answered!

 

[Mcalata]

I agree with the above post, when I looked at the pictures I thought it was light bleaching too although it does look a little odd to me because of the rusty look. I have zero experience with LEDs but from reading other people's posts I've come to understand that you want to keep LED's further from the plant then typical with other types of high intensity lights. I can see where a lot of people might make this same mistake if they switch from MH and HPS HIDs to LED's with HIDs it tends to be more about the heat even though it's really the intensity. What I mean is once you get them far enough away where it doesn't feel too hot (usually around 24 inches) that's far enough to protect from the intensity. With LED's being low heat I can see where people would assume they can put them closer then HIDs but it ends up being too intense even though it's not too hot.

Yup, led's run super cool compared to hps and on my last run I was able to run them at about 10 inches (slightly under %100 power) with no problem. I guess i just got too confident and the light intensity was too high. Thanks for answering!

 

[Subu]

Let us know how it goes

 

[Mcalata]

I'm without the clues I need. I see light green tops often associated calcium deficiency at switch. Standard stuff. The lines look like pH troubles, but I think it's more about the big jump in light that highlights they carried an inappropriate set of reserves. They just fell apart.

Sup f-e, yeah I've been meanin to get a watt meter but they are not that comon where I live at.

So the light green tops are normal when fliping them to flower, should I up the calcium? Cause im using RO water at 30ppm (my tap water comes out at 1200-1400ppm) and I usually use calmag to get my base water to 200-300ppm

Once again thanks for the replies!

 

[Mcalata]

Let us know how it goes

Definitely will

 

[Mcalata]

Super setup Mcalata! When I add or use high-wattage LEDs I bump up the cal-mag. The cal-mag protects the leaf tissue by strengthening the cell walls.

Hey, thanks! I'm using calmag at about 200-300ppm and haven't had deficiency yet. Thanks for the tip

 

[f-e]

Sup f-e, yeah I've been meanin to get a watt meter but they are not that comon where I live at.

So the light green tops are normal when fliping them to flower, should I up the calcium? Cause im using RO water at 30ppm (my tap water comes out at 1200-1400ppm) and I usually use calmag to get my base water to 200-300ppm

Once again thanks for the replies!

Can you mail order lux meters? This post is quite good, though I'm a bit bias https://www.icmag.com/forum/marijua...pfd-v-lux-readings-help-me/page3#post17834396
While we can use lux meters, it is primarily camera stuff. If the postman announces he's into photography, then your brother wanted one on holiday. Giving you a Christmas gift idea. It's not a suspicious item.

The light colour at flip is seen in most gardens. It can be relieved with a foliar spray, but 99.9% of folks just ignore it. It only lasts a few days. The issue arises as the plant in the full swing of growing, is suddenly left in the dark. It carries on growing, using up what is available. It can't get Ca though as transpiration slows. It's a bit mystical to me tbh. I was spraying Ca for this reason a few days ago. It seems to need it every night though, and the gain is small. I like to do it the first couple of nights of transition. Then loose interest.

 

[Mcalata]

Can you mail order lux meters? This post is quite good, though I'm a bit bias https://www.icmag.com/forum/marijua...pfd-v-lux-readings-help-me/page3#post17834396
While we can use lux meters, it is primarily camera stuff. If the postman announces he's into photography, then your brother wanted one on holiday. Giving you a Christmas gift idea. It's not a suspicious item.

The light colour at flip is seen in most gardens. It can be relieved with a foliar spray, but 99.9% of folks just ignore it. It only lasts a few days. The issue arises as the plant in the full swing of growing, is suddenly left in the dark. It carries on growing, using up what is available. It can't get Ca though as transpiration slows. It's a bit mystical to me tbh. I was spraying Ca for this reason a few days ago. It seems to need it every night though, and the gain is small. I like to do it the first couple of nights of transition. Then loose interest.

Let us know how it goes

Sup guys!?

So you were right, it was definitely light burn. They have been growing like crazy and there is no sign of any kind of deficiency or other problem. So big thanks for that!

Now I've been debating, should I defoliate them or are they ok like this?