Burnt tips any help is appreciated

[Howdyhomieimtony]

Hey everyone I’m growing six plants in a 4x4x7 tent, I’m running general hydroponics flora series, 5 gallon fabric grow bags coc coir with added dynomyco. I also use fish shit every other watering I’m using a sf7000 light with supplemental UV and IR temps in tent never go above 77 or below 68 degrees lights are about a foot and a half from tallest plant I ph every feeding to 6.1. It is currently week 6. I think some plants are showing signs of light burn and some are not is this just a symptom of the UV light, recently I’ve started doin 1 hour before lights off any help is appreciated.

 

[RGWD0202]

Hey everyone I’m growing six plants in a 4x4x7 tent, I’m running general hydroponics flora series, 5 gallon fabric grow bags coc coir with added dynomyco. I also use fish shit every other watering I’m using a sf7000 light with supplemental UV and IR temps in tent never go above 77 or below 68 degrees lights are about a foot and a half from tallest plant I ph every feeding to 6.1. It is currently week 6. I think some plants are showing signs of light burn and some are not is this just a symptom of the UV light, recently I’ve started doin 1 hour before lights off any help is appreciated.View attachment 2574571View attachment 2574570View attachment 2574569
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Looks like light burn with the leaves curling up, nutrient toxicity is usually clawing of the leaves. I don’t know enough about the supplemental lighting so can’t help with the UV. What is your ppfd?

 

[Howdyhomieimtony]

Looks like light burn with the leaves curling up, nutrient toxicity is usually clawing of the leaves. I don’t know enough about the supplemental lighting so can’t help with the UV. What is your ppfd?

Thanks for responding tops of the tallest plants are are a little over 1000 but I don’t know how reliable my meter is, I also only run the supplemental UV 1 hour before lights off and IR 15 min after lights off

 

[RGWD0202]

1000ppfd isn’t going to do that I don’t think. I don’t use co2 and I’ve been above that without that kind of burn but some strains are more sensitive than others. The Photone app is pretty close to accurate if you aren’t using that try the Photone app, $6 for iPhones free on android I believe but make a diffuser using a piece of printer paper. What week of flower are you in?

 

[Howdyhomieimtony]

1000ppfd isn’t going to do that I don’t think. I don’t use co2 and I’ve been above that without that kind of burn but some strains are more sensitive than others. The Photone app is pretty close to accurate if you aren’t using that try the Photone app, $6 for iPhones free on android I believe but make a diffuser using a piece of printer paper. What week of flower are you in?

Just started week 6, I’ll definitely try the app

 

[ChairmanFester]

Try 800 to be safe tbh, I start there. It looks like light burn.

 

[Howdyhomieimtony]

1000ppfd isn’t going to do that I don’t think. I don’t use co2 and I’ve been above that without that kind of burn but some strains are more sensitive than others. The Photone app is pretty close to accurate if you aren’t using that try the Photone app, $6 for iPhones free on android I believe but make a diffuser using a piece of printer paper. What week of flower are you in?

Currently week 6, I’ve just downloaded the photone app. Will update after I try to use it

 

[LoveGrowingIt]

A possible cause of leaf tip chlorosis or necrosis is VPD being too high. What can happen is transpiration so high that water and nutrients don't reach the end of the leaves. It does look like the light might be too intense, though, so reducing it is likely to help. There's also indication of N deficiency (chlorotic leaf ends) and P deficiency (necrotic leaf edges). So, I'm thinking nutrient problems.

What are you using for your root zone?

What's your target VPD?

 

[LoveGrowingIt]

I’ve just downloaded the photone app. Will update after I try to use it

I use Photone and like it. I also bought the diffuser. I close the tent except of a small part above the light because I noticed the reading can change a lot depending on whether the door is open or closed. I mostly use the app for young plants or when I'm moving a plant to a different tent.

 

[Howdyhomieimtony]

A possible cause of leaf tip chlorosis or necrosis is VPD being too high. What can happen is transpiration so high that water and nutrients don't reach the end of the leaves. It does look like the light might be too intense, though, so reducing it is likely to help. There's also indication of N deficiency (chlorotic leaf ends) and P deficiency (necrotic leaf edges). So, I'm thinking nutrient problems.

What are you using for your root zone?

What's your target VPD?

Currently I’m using general hydroponics flora series 10 part system plus diamond nectar and flora nectar, fish shit every other feeding

Aiming for 1.2 VPD but it stays around 1.5-1.7

Any thoughts on the UV light being part of the problem?

 

[pnwbluntman]

You are checking your ec? And 1000 ppfd is too high with out running CO2. You would be better off at 800-700 ppfd. There is a window where you can utilize CO2 and bump up the light. Light stress is usually where the whole leaf turns pale and losses chlorophyll. To me it looks like you are running to much nitrogen this far into flower with that strain you have. I would check you run off and match the ec level to which week of flower you are in

 

[LoveGrowingIt]

Currently I’m using general hydroponics flora series 10 part system plus diamond nectar and flora nectar, fish shit every other feeding

Medium? (Like soil or coir, for example.)

Aiming for 1.2 VPD but it stays around 1.5-1.7

That's high enough to starve the leaf tips. Unfortunately, the yellow leaves won't turn green again. There's also some yellowing between the veins of some of the older leaves. That's usually related to Mg deficiency and/or light intensity. Reducing the light should help. Adding Mg should help, too. For a Mg amendment, I use Epsom Salt or Dolomite Lime, depending on the pH of my soil.

I think what I'd do with those is lower the light intensity and try to get the VPD in the 1.2 to 1.3 range.

Any thoughts on the UV light being part of the problem?

I doubt it, but that's a question for someone who knows more about it than I do. I haven't grown with UV light. I've only read about it and decided that for my growing style it's probably too much trouble. That could change.

 

[Howdyhomieimtony]

Medium? (Like soil or coir, for example.)

Growing in coco.

That's high enough to starve the leaf tips. Unfortunately, the yellow leaves won't turn green again. There's also some yellowing between the veins of some of the older leaves. That's usually related to Mg deficiency and/or light intensity. Reducing the light should help. Adding Mg should help, too. For a Mg amendment, I use Epsom Salt or Dolomite Lime, depending on the pH of my soil.

Definitely will be lowering VPD. Will Epsom salt or Dolomite lime work with my general hydroponics salt based fertilizers?

1000ppfd isn’t going to do that I don’t think.

Photone app said I was running over 1100, I’ve lowered it to around 800

You are checking your ec?

No, being 100% honest my meter reads in ppm and I don’t know if it’s the 500 or 700 scale so I can’t do the calculations. I’ll have to do more research.

 

[pnwbluntman]

Just error on the light side of feeding until you get it figured out, cannabis usually tends to grow better with less.

 

[LoveGrowingIt]

Growing in coco.

Okay. I asked because of the pH. You've got it right for coir, AFAIK.

Will Epsom salt or Dolomite lime work with my general hydroponics salt-based fertilizers?

I don't use those fertilizers, so I don't know. Some of my organic growing mindset showed itself. Someone familiar with your growing methods should answer this one.

Photone app said I was running over 1100, I’ve lowered it to around 800

That should help. When growing outside, the light changes as the growing season nears its end. So, less light is what the plants expect.

Be careful about changing too many things at once give the plants a few days to a week to adjust. Reduced light should help a lot.