Burn from excess light?

Good afternoon, first of all I apologize for my bad English.

From your point of view, can this be light burn?
I currently have 8 cree cxb 3590 led working at 2.0 amp each led approximately
I had the lights at a distance of 40cm, and I raised them but I am worried about the color that the tips of the plants took.
I am currently working with an EC of 0.9 / 1.0. I always keep the pH stable within 5.7 to 6.0.


I had a slime problem, but it's under control thanks to Heinserberg tea.

your RH% is only 16?

and what temp is at the canopy level? 22.9C is above the lights.

and are you sure the tea fixed your root problems completely?

To much light and to low humidity. I've never had success running teas and other organics in hydro. The only real supplement I would recommend is SouthernAG containing bacillus amyloliquefaciens if you live in the states.

Many people use oxidizers with great success and that's what I always used to prevent root rot. Like bleach (sodium hypochlorite) at 3 ppm residual. Here's the calculator I've always used:
Chlorine dilution calculator

That is the temperature and humidity at the height of the plants, they do not usually vary more than that. I am treating the root problem, although it is not completely solved yet but it is improving.

No Habla.

rkymtnman said:

No Habla.

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Edit sorry

below it is in the process of recovery, I am treating it with hummus tea and great white heinserberg style.

Mattossz said:

although it is not completely solved yet but it is improving

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try to fix your root issue 100%. that could be causing the issues you are seeing.

also, your lights off temps are pretty low 17.5C=63F

like @Wastei said, i would dim your lights too if you can until you get the root issue fixed.

if the tea doesn't fix it in a few more days, i would try a different method for root rot. chlorine, peroxide, etc

Thank you very much for the advice, I am going to solve the problem that the temperature varies and give more focus to the roots. I'll be updating the topic in a few days

Mattossz said:

Good afternoon, first of all I apologize for my bad English.

From your point of view, can this be light burn?
I currently have 8 cree cxb 3590 led working at 2.0 amp each led approximately
I had the lights at a distance of 40cm, and I raised them but I am worried about the color that the tips of the plants took.
I am currently working with an EC of 0.9 / 1.0. I always keep the pH stable within 5.7 to 6.0.


I had a slime problem, but it's under control thanks to Heinserberg tea.

Click to expand...

Nutrient issues.... or ph... not lighting

Mattossz said:

Thank you very much for the advice, I am going to solve the problem that the temperature varies and give more focus to the roots. I'll be updating the topic in a few days

Click to expand...

Defo a good idea... just get a water cooler will sort it right out. We'll worth it if your committed to dwc

oill said:

Nutrient issues.... or ph... not lighting

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I just restored my ph meter to factory values, also new calibration 4 and 7, I see that my solution is in 6.4
I estimate the problem comes from this side mate. Thanks a lot

Mattossz said:

I just restored my ph meter to factory values, also new calibration 4 and 7, I see that my solution is in 6.4
I estimate the problem comes from this side mate. Thanks a lot

Click to expand...

Sounds right.... I calibrate every time I mix my 250ltr tank.... basically every week. Can't be fucked to mix it badly... Best to check every time

oill said:

Sounds right.... I calibrate every time I mix my 250ltr tank.... basically every week. Can't be fucked to mix it badly... Best to check every time

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Good afternoon friends, I just checked that my ec meter (Chinese) was super bad, it gave 0.3 ec higher than it really was. Could it be a nutrient lockout because of this too? I just bought a new one

when you have rot, i would try to dim lights and reduce EC. the plant is not functioning at full capacity.

Mattossz said:

Good afternoon, first of all I apologize for my bad English.

From your point of view, can this be light burn?
I currently have 8 cree cxb 3590 led working at 2.0 amp each led approximately
I had the lights at a distance of 40cm, and I raised them but I am worried about the color that the tips of the plants took.
I am currently working with an EC of 0.9 / 1.0. I always keep the pH stable within 5.7 to 6.0.


I had a slime problem, but it's under control thanks to Heinserberg tea.

Click to expand...

Great choice on lighting. Those cree COB's are bad to the mothafuckin bone. You definitely have a root issue but your foliage damage is a fine example of LED light burn. You could try adding 35% H202 at 4ml/gallon to your buckets along with your fertilizer. That should sterilize the roots within 3-5 days. You're definitely hitting them with too much light. Toss small plants like that under an HID and you'll see a very similar effect. 99% of the time these pictures get posted with this type of question people incorrectly advise others to adjust their fertilizer input. Almost every new LED grower will burn their plants because it's unlike any other kind of lighting and most of the manufacturer's really suck at telling their customers how to properly use the equipment without scorching their plants. I've got 2 110w qb's dimmed to 60% in a 5x5 and the nursery girls love it. Lush foliage with leaves pointing to the light. Less is more with LED. If it looks intense to the naked eye and the leaves are yellowing showing chlorosis dim the light and raise it. These aren't flourescant fixtuers that need to be mounted right over the plants. LED boards also emit too little heat to maintain the ideal grow room temperature. The garden should always be 77F-82F. Any lower and the plant won't drink fast enough to absorb enough fertilizer. Gotta keep the temp in check and your plants will respond positively. Check out @DoubleAtotheRON and his garden. His 480w HLG boards are what looks to be 6' or 7' above the canopy. His results speak for themselves.

jonnynobody said:

Great choice on lighting. Those cree COB's are bad to the mothafuckin bone. You definitely have a root issue but your foliage damage is a fine example of LED light burn. You could try adding 35% H202 at 4ml/gallon to your buckets along with your fertilizer. That should sterilize the roots within 3-5 days. You're definitely hitting them with too much light. Toss small plants like that under an HID and you'll see a very similar effect. 99% of the time these pictures get posted with this type of question people incorrectly advise others to adjust their fertilizer input. Almost every new LED grower will burn their plants because it's unlike any other kind of lighting. I've got 2 110w qb's dimmed to 60% in a 5x5 and the girls love it. Lush foliage with leaves pointing to the light. Less is more with LED. If it looks intense to the naked eye and the leaves are yellowing showing chlorosis dim the light and raise it. These aren't flourescant fixtuers that need to be mounted right over the plants. LED boards also emit too little heat to maintain the ideal grow room temperature. The garden should always be 77F-82F. Any lower and the plant won't drink fast enough to absorb enough fertilizer. Gotta keep the temp in check and your plants will respond positively. Check out @DoubleAtotheRON and his garden. His 480w HLG boards are what looks to be 6' or 7' above the canopy. His results speak for themselves.

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Thank you for your response, I am currently cutting off all affected roots and I am waiting as the situation continues. It does not look good since the problem started in rock wool.

Mattossz said:

Thank you for your response, I am currently cutting off all affected roots and I am waiting as the situation continues. It does not look good since the problem started in rock wool.

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Take clones and start over. Maybe a different medium? There's always a way out of a tight situation Keep on trucking dude. Every failure is a learning experience.

Just looking at at the pics and info..... I'd say too much light. You also have a possible Cal/Mag deficiency. LED requires a bit more of it. Get a good PH meter (they're worth every penny),.. Id recommend the Apera 8500s .. Most people problems are PH related, and they have no accurate way to measure this at the root zone. IF you don't have a good PH (root zone meter), then you'll be like everyone else, and start throwing shit at it that will compound the problem. Most of the time, it's as easy fix. You just need one good tool that I promise will make your growing easier.
This one.... https://aperainst.com/apera-instruments-ai3211-ph8500-sl-portable-ph-meter-tester-for-soil-direct-measurement-equipped-with-labsen-553-electrode-plastic-lead-free-glass.... and you gotta get that RH under control. Get a Portacool evaporator cooler to add moisture to the room.

Mate, if you're going to do that much work setting up hydro, I reckon you could do yourself a favour and not have the roots drowning in a little reservoir. You want to see a springy mass off roots. There are various ways to go about this, but definitely think about a redesign, then 80% of your problems will magically vanish with the minimum of work.