Is this magnesium deficiency?

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Aqua Man

Aqua Man

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Its your temps man. 64 with the lights on? just way to cold in there. I'm sure that was your issue from the start. and still is, i bet your leaf temps are mid to high 50's
 
Cdub97

Cdub97

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Oh and I’ve switched to Citric acid to ph my well water. 1.25 teaspoons brings it from around a 6.8-7 down to 6.2-6.4
 
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Cdub97

Cdub97

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Its your temps man. 64 with the lights on? just way to cold in there. I'm sure that was your issue from the start. and still is, i bet your leaf temps are mid to high 50's

ok but....


I’m keeping it consistently at about 69F. Space heater right on top of them. You can see it to the left there.

I opened up a door to the basement from the rest of the cold ass house and it dropped.

In general it’s 69-70. But I ought to build a plastic screen house in here. It’s too drafty.
 
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Cdub97

Cdub97

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I’ve decided to build a tent for my veg area using 1” pvc, corner bits, and plastic sheeting. Looks like I can do it for about $65 for a 10x6x4 rectangular box.

I gotta get a handle on temps and this way I think I can run one of those efficient low powered tubular greenhouse heaters.
 
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Judaz

Judaz

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hmm. I'm speculating light stress and maybe heat issues on plant leaves. If you got one of those laser thermometers take temp of those leaves on tops. I've seen this before in plants with under developed root systems and not being able to handle light intensity in the beginning. get a par meter if possible and measure light levels on top of canopy. also don't like the 81.5 temps with humidity in low 30's. You setting up for failure and all sorts of problems
 
Cdub97

Cdub97

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hmm. I'm speculating light stress and maybe heat issues on plant leaves. If you got one of those laser thermometers take temp of those leaves on tops. I've seen this before in plants with under developed root systems and not being able to handle light intensity in the beginning. get a par meter if possible and measure light levels on top of canopy. also don't like the 81.5 temps with humidity in low 30's. You setting up for failure and all sorts of problems

My temps are usually in the mid to upper 60’s in here. Humidity varies between 50-70% or so. As I mentioned I’m going to build a plastic sided tent to get things more stable.

ITS THESE LIGHTS. (and the associated lower temps). All these plants were perfect under metal halide. Then, I switched to led and outside temperatures also dropped significantly leading to even lower temps in the grow room . These led’s don’t emit much heat themselves and the spectrum is way different.

There is no heat stress on the leaves that is certain. These root systems are quite developed. All these plants have been low stress trained as well. I played around with a light intensity meter on my phone a few times and I’m pretty sure I’m at an acceptable distance although yes....I need a real lux meter.

A couple of them look great again but one is still way off. All these big plants are gonna get flowered soon so I’m going to keep trying to get it dialed I better moving forward with my smaller clones that aren’t in fabric pots yet. Actually a few of the smaller ones are suffering a bit too. I’m pointing towards the affected ones in the pic.

Fingers crossed that by building a tent, more tightly controlling my heat and humidity levels, and perhaps a good liquid calcium foliage supplement will get everything in check.
 
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Cdub97

Cdub97

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All things aside...this is my first REAL attempt at growing...I did it 3x before but it was a joke by comparison. I’m doing alright as amateur as a I am. Here’s a girl in flower. 15 gallon pot. I just put in the bamboo stakes in last night.
 
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Jimster

Jimster

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I would try to warm up the roots a little. When temps drop, the roots don't stay nearly as warm... especially if sitting on cement. The higher humidity might be keeping the soil damp and keeping it cooler as a result. Also, the plant with the droopy leaves might simply be reacting to the position of the light source, being more off the side compared to the others that appear to be directly under the lights. The leaves will grow to catch as much light as possible... I have had some grow upside down after growing taller than the HID bulb.
 
Cdub97

Cdub97

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I added a 250w heat lamp to keep temperatures more even until I build a tent.

There’s something wrong with the one in the middle and the two smaller clones in front of it look bad too.

They’re not on concrete. It’s carpeted in here.

Just wilty, and now I’m getting some crazy looking discoloration and purpling of the stalk just keeps spreading.

It’s not reacting to the light position. The coverage is ridiculous from these huge fixtures.
 
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Beachwalker

Beachwalker

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My well water is around a 6.8 or higher if I don’t PH all my water. Honestly since growing on this water is new to me I’m just doing it because I thought I must. I figured those fancy ph-down products were just phosphoric acid solutions anyhow. It takes me about 4 TABLESPOONS of vinegar per 5-gallon bucket to get it to about 6.2. Seems like it’s a bad idea. Again, I need to do more testing of my soil runoff.

I’m using fabric sided smart pots and they dry out pretty fast so I don’t think I’m overwatering. I only water every 2-3 days and I usually stick my finger in the soil or lift the plant to see if it’s dry first.

You can kinda see it affecting several of the tips of leaves in the group pic. Oddly these problems of dropping leaves, the loss of dark green color near the leaf veins, and increased purpling and redness on leaf stems and stalks have all gotten worse under these industrial 5K led fixtures. I upgraded my veg area to them to save electricity and this way I was able to put both my hid ballasted lights into my flowering room. Something about these lights is either a little deficient or it’s putting an additional nutritional drain on the plant that I’m not compensating for.
6.2 too low for soil, use 6.5
 
Beachwalker

Beachwalker

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It’s over watered. And root zone is locking out causing deficiencies. Suggestion, to allow media to dry out. Also ph swings cause a lockout as there is a finite range for certain nutrient availability and plant uptake. Container size is also key, start small and up pot to avoid drowning the root zone. Few charts attached to help ya
^

I have no idea and I don’t even know how to find out.
ppm meter, 10 bucks

Also add the 400 mh light back. I would ditch those lights and go with two 400 or 600 watt HID light instead in an area that size
 
Devotion1

Devotion1

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you can buy a grow tent on amazon for $100 or less for the size you want, building your own will be a waste imo, I tries it myself years ago with pvc and it didnt work well or last
 
Cdub97

Cdub97

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you can buy a grow tent on amazon for $100 or less for the size you want, building your own will be a waste imo, I tries it myself years ago with pvc and it didnt work well or last

🤷‍♂️🤷‍♂️🤷‍♂️ It’s 1” pipe (which a pretty sturdy) and corner pieces. I’m not hanging anything off it. The lights are suspended from the ceiling. It’s just a frame for plastic sheeting.

My needs are simple and this will be fine....also 10x6x4 is not a $100 tent....maybe a 4x4 is $100.😐 I’m looking at $60 for pipe, corners, and plastic sheeting.
 
Jack og

Jack og

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Omg guys! Improvement!!!

One night with a 250w heat lamp on top of them all night and I’m seeing a drastic change!

I guess those 60 degree temps were way too low!
Major phosphorus deficiencies. Boost her up! Those purple stems will lead to issues in flower
 
J

Jaydee86

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Hi guys did you ever get to the bottom of this issue?
I would have a bet and tell you that the intensity of light from the led is wayy too much!
Let me know if you ever sorted it out?
 
T

TryingToGrow

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For me, growing medium (soil, coco, organic soil, etc. doesn't matter), needs to be 5.8-5.9, or very close, if I want my plants to grow well. It can go off a little, but as soon as notice anything more than 0.2 pH off, that's a problem (imo), and I top dress with powdered lime or pelletedized lime for up or epsom salt for down, lots of other stuff but those 2 are easy, to get back into acceptable pH range.

Unless outside in the veggie garden, I always need to pH my city tap water (300 ppm, 7.5 pH), to 5.7 and let it sit for a couple days before using then recheck and readjust pH, before using. Even there, for some plants to grow well, my peppers and stuff that also like low pH acidic soils, I need to start to do something about pH so they will grow better, actually have now. Most of me lettuce and kale, as well as some others don't mind the high pH. I always pH a little lower since it always seems like everything is trying to go up.

I have been adding elemental sulfur, espom salts, gypsum, wood chips, etc. to help lower the pH in my veggie gardens over the off season. I think it's best to not add so much of just one thing to the medium in to short a time period.
 
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