Toxicity/Deficiency? Need a little guidance please

[pg2052]

Hey all - so I'm middle of week 6 with an Amnesia Haze Auto from ILGM. I've got 3 plants total, the other two are quite tall -- the one that's giving me issues at the moment, is very short and bushy. Only about 12 inches (the other 2 are pushing 36 inches). The short, stocky one has been looking pretty good to date -- albeit a good bit slower to develop than the other 2. Nice shade of green and perhaps just now starting to stretch a little. In any event, noticed a couple of brown spots when the lights came up this morning.

I'm in a soil/coco/perlite medium (60/30/10) in 3 gallon rain science bags. I'm using fox farm's macro trio, at about 1/4 strength -- 450 ppms was last night's feed (and that's with about 130 in the city water). Fed some tiger bloom nutes last night (for the first time) as well as some grow big (was planning on that being the last time). Probably a little early for the bloom nutes on this plant, but the other 2 were past ready and frankly I just didn't have time to mix up separate batches. I only started feeding nutes about 2 weeks ago. Feed/water/feed/water. I'm using city water, pH'd down to about 6.3-6.5 range. City water runs at about 130 ppms on average (last report I saw indicated 30 ppms of Ca and 10 ppms of Mg).

Gear - HLG 260xl was about 24 inches above plant at issue, cranked to about 230 of 280 available watts from wall. I backed the light off quite a bit this evening to about 35 inches and powered it down to about 185 watts (just in case that was causing any issues). I'm in a 2x4 tent running a Cloudline T6 inline exhaust fan with Carbon Filter; passive intake; couple desk fans pushing air around; Temps: 72-74 during the day; 63-65 at night; RH: of about 45-55.

Any ideas what I might be dealing with and how to address? I've tried to be super cautious about feeding because I think I overfed last grow. Maybe I need to ease off even more? Or maybe I'm not feeding enough? I know it's just a couple of spots at this point, but I'd really like to nip this in the bud (pun intended) if possible.

Thanks in advance!

 

[pg2052]

Also I should note that many of my fan leaf stems are turning purple.

 

[Mañ'O'Green]

@pg2052 Looks like you are headed for a lock-out usually from too much of something. The first problem is the 60% soil 40% hydro base. Coco needs to be rinsed or it will build up salts. But the soil should not be rinsed? The problem looks like Phosphorus or calcium lock-out.

Based on what I am seeing I am going to say too much Cal-Mag.

 

[pg2052]

@pg2052 Looks like you are headed for a lock-out usually from too much of something. The first problem is the 60% soil 40% hydro base. Coco needs to be rinsed or it will build up salts. But the soil should not be rinsed? The problem looks like Phosphorus or calcium lock-out.

View attachment 1297422

Based on what I am seeing I am going to say too much Cal-Mag.

Thanks for taking a look! I’m not feeding any CalMag - other than whatever might be in the ocean forest and my city water. You think the soil/water could be hot enough to create a CalMag issue?

 

[Mañ'O'Green]

Liquid Concentrated Nutrient. General Hydroponics FloraMicro (5-0-1) is the foundation or “building block” of the Flora Series system. Provides nitrogen and calcium as well as trace minerals which are essential for a comprehensive hydroponic plant diet. Combine with FloraGro and FloraBloom to meet the specialized needs of each phase in a plant’s life cycle: seedling, vegetative, transitional, flowering and fruiting.

You are running hydroponic nutrients in soil? Go here to get a better understanding of what I mean by balance.

Tutorial - A word on Nutrients

The proper use of “salt” based fertilizer to grow Auto Flowering Cannabis. Salts: Natural and man made any chemical compound formed from the reaction of an acid with a base, with all or part of the hydrogen of the acid replaced by a metal or other cation. Learning how to use salt based...

www.autoflower.org

You need at minimum the items in the red box always added in balance.

 

[pg2052]

Liquid Concentrated Nutrient. General Hydroponics FloraMicro (5-0-1) is the foundation or “building block” of the Flora Series system. Provides nitrogen and calcium as well as trace minerals which are essential for a comprehensive hydroponic plant diet. Combine with FloraGro and FloraBloom to meet the specialized needs of each phase in a plant’s life cycle: seedling, vegetative, transitional, flowering and fruiting.

You are running hydroponic nutrients in soil? Go here to get a better understanding of what I mean by balance.

Tutorial - A word on Nutrients

The proper use of “salt” based fertilizer to grow Auto Flowering Cannabis. Salts: Natural and man made any chemical compound formed from the reaction of an acid with a base, with all or part of the hydrogen of the acid replaced by a metal or other cation. Learning how to use salt based...

www.autoflower.org

You need at minimum the items in the red box always added in balance.
View attachment 1297426

I'm running Fox Farm Macronutrients: Grow Big and Tiger Bloom

Tiger Bloom is:
Guaranteed Analysis
Total Nitrogen (N)……….2.0%
0.10% Ammoniacal Nitrogen
1.90% Nitrate Nitrogen
Available Phosphate (P2O5)……….8.0%
Soluble Potash (K2O)……….4.0%
Magnesium (Mg)……….0.5%
0.5% Water soluble Magnesium
Contains Trace Minerals
Boron (B)………..0.02%
Copper (Cu)……….0.05%
0.05% Chelated Copper
Iron (Fe)………..0.12%
0.12% Chelated Iron
Manganese (Mn)……….0.06%
0.06% Chelated Manganese
Zinc (Zn)……….0.05%
0.05% Chelated Zinc
Derived from calcium nitrate, magnesium nitrate, ammonium nitrate, ammonium posphate, potassium phosphate, potassium nitrate, earthworm castings, kelp, iron EDTA, zinc EDTA, manganese EDTA, copper EDTA, chelating agent, disodium ethylenediamine tetra acetate (EDTA), and sodium borate.

Grow Big (couldn't find the ratios online):
Ingredients: Ammonium sulfate, ammonium phosphate, urea, blood meal, potassium nitrate, potassium sulfate, earthworm castings, Norwegian kelp, iron EDTA, zinc EDTA, manganese EDTA, copper EDTA, chelating agent, disodium ethylenediamine tetra acetate (EDTA), sodium borate and sodium molybdate.

 

[Proph]

Where are all these people getting this idea to mix coco and soil together?? Is it some YouTube person? I don't get it.. If coco and soil worked well together companies would sell it in bags pre mixed.
The issue is that you have mixed two completely different mediums together. I have never seen a coco mixed with soil grow that didn't have issues. Where did this idea come from?

 

[pg2052]

Where are all these people getting this idea to mix coco and soil together?? Is it some YouTube person? I don't get it.. If coco and soil worked well together companies would sell it in bags pre mixed.
The issue is that you have mixed two completely different mediums together. I have never seen a coco mixed with soil grow that didn't have issues. Where did this idea come from?

Not sure where other people get it from...but this guy does it on every grow with strong results: https://growdiaries.com/diaries/37355-morning-lemon-ak-47-collaboration/week/176760

 

[pg2052]

His write-up:

The ideal mix for auto flower plants should not be overly rich, but be moisture retentive yet well-draining and airy to allow more oxygen to the root-zone. Naturally it needs to be of the proper ph. range for your roots to absorb nutrients efficiently and not completely breakdown during the course of your grow. Using a mixture of organic composted products with a soil-less peat and coco coir-based products in combination with added perlite/pumice for a faster draining mix will create an excellent home for not only the roots but also for beneficial bacteria and mycorrhizae you will be adding to bring your soil to life.

I know what you’re saying to yourself why not just use straight organic or straight soil-less? The added organics will definitely add the essence of the materials used. This will add more flavor to your finished product not only is this truly Cannabis’s natural growing medium it will add some balance to your hybrid mixture. Yes, hydro/ coco coir grown weed will get you stoned but how much extra flavor does it really have compared to your soil grown weed? That’s purely a matter of opinion. Basically, we’re taking the best of both worlds.

I’m using three popular brands located in my area. You can substitute brands with similar ingredients if these exact brands aren’t available in your area. For my organic “essence” mix I’m using Fox Farm Ocean Forest which has composted forest humus, sphagnum peat moss, earthworm castings, bat guano, kelp meal, fish emulsions, shrimp and crab meal, oyster shell, perlite. It’s considered by many to be a “hot mix” meaning it is capable of causing nutrient burn on seedlings and young plants if used as a standalone potting mix. For my soil-less components Canna Coco Coir which is an excellent ready to use well-draining product which has been properly washed and buffered. BioBizz Light which is fine peat-based mix with a light nutrient content. It can hold a lot of water and can be a bit on the mucky side when used alone in my opinion. Some already contain a bit of perlite but we will add some more for improving drainage based on our personal watering habits for the best results. They all claim to be optimized for ph. a claim which should always be questioned/tested. Since we’re creating a hybrid soil/soilless mixture 5.8 to 6.4 would work the best for nutrient absorption.

Our bulk potting mix: 32% Fox Farm Ocean Forest, 32% Canna Coco Coir,32% BioBizz light and 4% Perlite.
Seedling mix: 7-parts BioBizz light, 1-part coco coir,1-part perlite.

 

[Proph]

Not sure where other people get it from...but this guy does it on every grow with strong results: https://growdiaries.com/diaries/37355-morning-lemon-ak-47-collaboration/week/176760

Those aren't strong results.. They are exactly what I expected to see.. Sick plants with fading leaves by week two of flower... Crispy yellow leaves at harvest. I went through 3 of his most recent journals. All the same issues starting in week 2 of flower. How far along is your plant? Even his write up is just a bunch of words. But back to your plant..
It's on its way to looking exactly like the ones in that guys journals. There isn't much you can do about it now. What you're seeing could be the result of any one of the multiple issues that are happening. The first thing that comes to mind is the ph of the coco/soil mix. I'm sure it's fluctuating. Next thing that comes to mind is the cec exchanges in the coco.. Coco has a low cec and leaches nutrients quite often.. It's probably releasing/exchanging too much calcium or phosphorus into the medium..(depending on what the coco was buffered with). Either way, the issue is with the medium, and there isn't a way that I've seen or know of to correct it. Maybe check the ph of the of medium if you have a soil probe.. I'm pretty sure it's either a nutrient lockout, ph lock out or both..