Light burn or deficiency progressing ?

[ReggieD]

Right so yesterday I have noticed on one of the plants leaves curling up etc. I concluded that it might be some sort of lockout causing possibly potassium deficiency. I had fed them with plain water and I’ve checked the runoff which came out between 7.4-7.8 so I have decided that for the next week I will feed them just with water to clear them out a bit. Anyways, yesterday I also set my light (Lumatek ats pro 300w led) from 75% to 100% and today I have noticed that some of the leaves developed some stains etc (see photos) so now I’m wondering if that is my issues progressing since yesterday or if it’s the light burn and I should dim it back to 75%. It’s weird cus it seems like only few of top leaves are affected. Problem is that distance from the light is 32cm (12 inch) and I can’t go any higher cus my bloody tent is 6ft (around 180). But that distance is from the tallest canopy, others are around 16 inches so I’m not sure if I should go back to run them at 75%.

Tent size is 3x3x6

Light ats Lumatek pro 300w

White widow

5th week of flowering

 

[BigBlonde]

It looks like light burn to me, especially because it happened after you turned up the lights. I also think nutrient problems tend to show on more of the leaf surface.

 

[ReggieD]

It looks like light burn to me, especially because it happened after you turned up the lights. I also think nutrient problems tend to show on more of the leaf surface.

Do you recon if I dim the lights back on 75% and run at this level till the end of the grow that would be sufficient for my area 3x3?

 

[BigBlonde]

Do you recon if I dim the lights back on 75% and run at this level till the end of the grow that would be sufficient for my area 3x3?

My thinking is that changes usually should be done gradually to avoid over stressing the plants. So, maybe dial it back to 75% and then increase by 5% or so a few days apart to give the plants a better chance to adjust.

 

[ReggieD]

Can’t really do that as I can only dim it from 75 to 100, there isn’t anything between :/ I’ve put it back on 75 and on Monday I’ll check them lights with lux meter to rule out light issues

 

[Zen_Seeker]

Picked up the North American version Photontek sq300w. Same issue. Yellow stripes that look like Manganese issue or start of light burn.

LED has been moved from 18” up to 36” and back to see if light burn is issue. At 20” now with LUX at 350 to 400 from one side to other.

Tent is 3x3 with one large bushy plant. Temp between 20* - 28* Celsius & 45% - 60% humidity.

Yesterday added Gaia Green Sand mixed with worm castings & fresh soil mix for about 2” of new soil on top of original soil. Soaked in with 500ml water spray.

PH is closer to 7 than I like but need a new/better meter.

First grow with this light. Plant was on Veg hold in another tent waiting to move. (Low light and topped twice before new tent was ready.)

NA company doesn’t have hight suggestions but the UK one does that you can DL in PDF.

 

[Zen_Seeker]

Here is the link for the PDF:
Lumatek Dropbox PDF

LUMATEK GROW LIGHT STRATEGIES.pdf

Shared with Dropbox

www.dropbox.com

Double checked the LUX now that the light is warm. Outside edges are at 370/380 LUX and middle is at 400 LUX. Canopy is between 18”/20”.
(Meter set to X100 so 37,000 to 40,000 LUX.) Model LX1330B - Dr Meter

Plant was grown from seed as an extra JIC in late September early October. Sitting vegging slow since October until new space ready. Just made 3 clones with it, all fine, different tent.

Testing LST and new LED combo on this older stronger plant. No info on strain but seems to be a good mix. Thought I’d try 6/2x3 and stretch out veg with this girl. Other than the yellow stripes coming & going it’s been good. Day 27 since transplant.

Plant transplanted to 25L soft pot and put into 3x3 26 days ago. Yellow started after a few days. Turned light to 50% for about two weeks then back to 75%. Seemed to help but slow growth. Now yellow seems to slowly spread across the top after a few days back at 75%. (The sq300w dimmer only supports 0%, 25%, 50%, 75%, & 100%.)

I’m hoping the soil treatment I noted above works as I’m at a loss do to everything being new and experimental.
(Forgot to add that 4-4-4 was mixed into the 2” soil top up earlier.)

 

[Trixie]

You have a nutrient imbalance which could be caused by a few different things. So it is hard to say without knowing more. My first glance says you burn the shit out of your plants adding a lot of stuff to the soil that didn't need anything. With every watering, you release the amended nutrients and its raised the salt content of the soil. The high salt level has caused the start of a lockout and pH fluctuations.

 

[GreenGalaxyFarm]

Picked up the North American version Photontek sq300w. Same issue. Yellow stripes that look like Manganese issue or start of light burn.

LED has been moved from 18” up to 36” and back to see if light burn is issue. At 20” now with LUX at 350 to 400 from one side to other.

Tent is 3x3 with one large bushy plant. Temp between 20* - 28* Celsius & 45% - 60% humidity.

Yesterday added Gaia Green Sand mixed with worm castings & fresh soil mix for about 2” of new soil on top of original soil. Soaked in with 500ml water spray.

PH is closer to 7 than I like but need a new/better meter.

First grow with this light. Plant was on Veg hold in another tent waiting to move. (Low light and topped twice before new tent was ready.)

NA company doesn’t have hight suggestions but the UK one does that you can DL in PDF.

looks drenched

 

[Zen_Seeker]

You have a nutrient imbalance which could be caused by a few different things. So it is hard to say without knowing more. My first glance says you burn the shit out of your plants adding a lot of stuff to the soil that didn't need anything. With every watering, you release the amended nutrients and its raised the salt content of the soil. The high salt level has caused the start of a lockout and pH fluctuations.

Soil is untreated Sunshine Basic 4 Mix.
Only thing ever added is worm casting.

Water is usually how I add nuts but trying dry nuts in soil topping as needed this time.

The yellow started after the move to the new tent before anything was added. (It did sit in low light for a month+ in a smaller pot so I assumed nuts had been used up.)

Not sure if a quarter cup of 4-4-4 dry mix added to 4L of soil to top 20L of untreated soil would be an issue? The 60ml of green sand mixed into old & new soil should be fine.

PH is an issue as most times I need to add 2cc/ml acid per 500ml water to stay between 6-7. Been using tap water left out for a day or more. Only have a crappy $20 meter but it’s been okay for over a year. New digital meter should come by end of January.

Was going to flip January 1st but now I’ll just watch and water as needed for next week. Hope I don’t need to flush.

Clones in other tent are fine and ready to start LST.

 

[Zen_Seeker]

looks drenched

Usually looks that way when lights first go on. Also sprayed with water that night after pulling down & tying off branches.

 

[Zen_Seeker]

With every watering, you release the amended nutrients and its raised the salt content of the soil. The high salt level has caused the start of a lockout and pH fluctuations.

Never had lockout before but after looking it up I’d say spot on. Quick search had a lot of pics showing same look.

As it started after the move it must have been the transplant. I must have used the wrong bin with old used soil waiting for compost I recycle. I remove most roots and larger crud and reuse in the vegetable garden after soaking on a tarp, or when necessary the plants.

Now I’m a little pissed the two shops I asked and showed pics to didn’t suggest this. I know one of them grows for sure.

Now I’m going to have to flush it after finding a big enough drip tray and researching a bit more. Son of a...

 

[Zen_Seeker]

Update 1:

Removed top soil added yesterday. Flushed and RO checked. All PH 7

Put about 1cm of top soil back to ensure roots covered. Watered and checked soil until both RO and soil read between 6-7. Most readings in soil a hair over 6.

Trimmed a few bottom branches and put it back in the tent. Fingers crossed.

 

[Zen_Seeker]

Update 2:

Plants still droopy but new growth over night. Canopy holes filled in. It’s at the point I want to flip, do to hight. Normally I’d wait a week before doing anything else but it wants to grow.

How long after this type of stress before I can flip?

Do any of the leaves affected return to normal colours? I’m assuming newish ones will but older ones won’t.

 

[BigBlonde]

Do any of the leaves affected return to normal colours?

The yellowing tells me the plant may be over watered causing nutrient lockout. I had that same type of yellowing and have a thread about it. I stopped watering and the plants recovered.

How long after this type of stress before I can flip?

I'm new to indoor growing, so I'm not very knowledgeable about when to flip. The plant certainly looks big enough to flip, but I would wait until it's healthy--maybe a week or so.

 

[Zen_Seeker]

The yellowing tells me the plant may be over watered causing nutrient lockout. I had that same type of yellowing and have a thread about it. I stopped watering and the plants recovered.

I’ve already flushed and put it back in. Now just waiting to see the results. Usually gets worse a day or two before things start to look better.

I’ll take a peek at your thread in case any extra ideas/info.

I usually wait a week after I break a branch or fix some issue. Just wondering if one week is enough time.

 

[RootsRuler]

Flipping stressed plants is the fastest way to harvesting a boatload of popcorn. Get your plant healthy first then flip her. If height is an issue strategically prune her after she gets healthy and flip.

 

[Trixie]

Make sure your plant canopy is getting hit with a nice breeze to keep the plant moving water. Plants with no air movement hold more water longer and can't transpire.

 

[Week4Bytch]

When did you start using the RO water ?

 

[Zen_Seeker]

Make sure your plant canopy is getting hit with a nice breeze to keep the plant moving water. Plants with no air movement hold more water longer and can't transpire.

Yep. Always on. Pointed at the side wall at the moment to avoid wind burn.

Turned the light back to 50% over night and she stretched so it’s back to 75% now.