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First coco grow -> very slow growth

Mikell

Dipshit Know-Nothing
ICMag Donor
Veteran
Having mycorrhizae spores in coco is a tell tale sign of snake oil-ism.

Coir is naturally inocculated with Trichoderma, which has a high tolerance for salinity.

Mycorrhizal fungi do not, nor do they function as intended (to increase soluble P in soil with tighly held P and increase water uptake during drought) in almost any medium we use.
 

repuk

Altruistic Hazeist
Veteran
Having mycorrhizae spores in coco is a tell tale sign of snake oil-ism.

Coir is naturally inocculated with Trichoderma, which has a high tolerance for salinity.

Mycorrhizal fungi do not, nor do they function as intended (to increase soluble P in soil with tighly held P and increase water uptake during drought) in almost any medium we use.

Sorry, I meant to say trichoderma is common on quality coco, my mistake! :bashhead:
 

ibreza

New member
Hey Snypie, what's up? Have you been feeding epsom for the last 15 days? If so your Mg def should have stopped its progression and your plants should be back on track. post some pics :)
 

Snypie

Active member
Hey ibreza, thanks for your interest. Unfortunately i stopped the Epsom feeding because i got many different positions... But i had to learn the difference... They were showing improvement when i was adding Epsom to the feed. So i returned 2 days ago to the Epsom feeding.
Today i transplanted the 3 bigger plant into 1 gallon fabric pot because i had to watering 2 times a day and became a decent root system.

I tried to make some pics but did not succeed. Tomorrow i will take some if there are better lighting conditions.
 

repuk

Altruistic Hazeist
Veteran
stay strong Snypie! once you dial in for your conditions it will be easy peasy!

Let them to recover, watch out specially new growth. Girls are much resilient than expected!

I have not grow for some time, I may be wrong but your girls doesn't look to me as if they were lacking Cal/Mag, but nitrogen, though I cannot see the bottom leaves, take a pic from the side so that the plants are standing upright relative to the viewer. Take close shots of new growth too.

This doesn't mean necessarily that you're not feeding enough N to them, it could be a different cause that is blocking N uptake (too low PH on the coco substrate, etc). If this were the case, a mild strength foliar application should enhance leaves appearance and help them to become lushier in the meanwhile until substrate stabilizes.

In any case, stay confident, and for best troubleshooting introduce few changes at a time, observe, then act.
 
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Snypie

Active member
Hy repuk,

The new growth was always great. This shit appears when the leaves become old and bigger and no matter where it is. But usually the middle and third top of the plant.

Now i have 2 PH pen and double check everything. PH 5.6-6.0 in, usually 5.8 and runoff PH is fluctuating between 5.6-6.2 also. Now it is 5.7-5.8. Seems to good. But the EC after flush is slowly climbing up. I am feeding with 600 ppm (1.2 EC) and the runoff EC is just between 330-650 (0.7-1.3 EC). I observed when the runoff EC is 1.7-1.9 the plants growing really well.
So what is the optimum runoff EC? Around 2.0 EC?

I did a foliar feeding with Spray mix (kelp based) + light Epsom a couple of hours ago. It always helped.

"until substrate stabilizes" Please explain out for me. Does this mean the substrate EC needs to go up around 1.8 EC?
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repuk

Altruistic Hazeist
Veteran
Hy repuk,

The new growth was always great. This shit appears when the leaves become old and bigger and no matter where it is. But usually the middle and third top of the plant.

Now i have 2 PH pen and double check everything. PH 5.6-6.0 in, usually 5.8 and runoff PH is fluctuating between 5.6-6.2 also. Now it is 5.7-5.8. Seems to good. But the EC after flush is slowly climbing up. I am feeding with 600 ppm (1.2 EC) and the runoff EC is just between 330-650 (0.7-1.3 EC). I observed when the runoff EC is 1.7-1.9 the plants growing really well.

OH, now I realize ppm -> EC conversion is different depending on the maker... 1.2EC is perfect.

So what is the optimum runoff EC? Around 2.0 EC?

I did a foliar feeding with Spray mix (kelp based) + light Epsom a couple of hours ago. It always helped.

"until substrate stabilizes" Please explain out for me. Does this mean the substrate EC needs to go up around 1.8 EC?
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Have done some mistakes already (feel rusty!) so will let others answer proper runoff EC.

What I mean with "until substrate stabilizes" is for coir to reach a chemically balanced state, where no lockout happens.

As you can read on the two reference posts I linked, unbalanced coco medium can "steal" or "block" certain nutes, rendering them unavailable to the plant, even when you are feeding plenty of them.

I would keep watching them, I think you're on the right track, and if this is the case you'll notice enhancements on plant health sooner than later.

Again I'm just talking from my own experience, but due to the dryness you were getting before, and judging the root-porn pic, plant roots weren't in their best shape, they need some time now that you fixed the watering cycles to develop their roots properly.

Something that always made my plants develop incredible roots was Rhizotonic by Canna, in fact I don't use cloning gels nor anything, just PH'ed water + rhizotonic at 0.7EC and got lovely, pure white hairy roots in couple days. I also give'em rhizotonic at 0.9EC when transplanting and never experienced transplant shock, it was me who was shocked how transplants induced explosive root growth in 24 hours. rhizotonic only on those waterings, no nutes.
 
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Miraculous Meds

Well-known member
It sounds like the cec wasn't set before you put the plants in.
I feed at about 1.2 to 1.4 max. Run off isn't a great indicator because of the ions that get trapped and released. You cant know what they are by measuring runoff. Try a slurry test. Take 100ml of coir from a couple different locations in your medium. Then soak it with 150ml ro or distilled water. Shake it, let it rest for 12 hours, then shake again, strain and measure the water ec and ph. That will give you a more accurate look at where your medium is currently at.
 

ibreza

New member
Don't stop feeding epsom and you'll be golden :D

It's no big mistery really, looking at Bionova coco forte, at 1.0EC with RO you're feeding ~20ppm Mg. That's not enough, plain and simple. that plus looking at your leaves, that's 2 distinct signs that you're missing Mg. I don't know why there is no consensus about this :dunno:
 

Snypie

Active member
Don't stop feeding epsom and you'll be golden :D

It's no big mistery really, looking at Bionova coco forte, at 1.0EC with RO you're feeding ~20ppm Mg. That's not enough, plain and simple. that plus looking at your leaves, that's 2 distinct signs that you're missing Mg. I don't know why there is no consensus about this :dunno:

OK, i watched my nutrient profile at angelfire nutrient calculator. I did this a few weeks ago. At 1.0 EC the profile is the following:
N: 90 ppm
P: 23 ppm
K: 88 ppm
Mg: 34 ppm
Ca: 129 ppm
S: 35 ppm

If i add 1 gr/gallon (~0.25 gr/l - i know you said 0.3 gr/l but i know the exact ppm for 0.25 gr/l) Epsom the solution will be:
Mg: 60 ppm
S: 69 ppm

The Ca is fucking high and the P is too low. It is confusing me. Or the calculator is wrong. Sorry ibreza, i know i am incomprehensible. I won't stop feeding Epsom. Thank you again ;)
 
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Absolem

Active member
OK, i watched my nutrient profile at angelfire nutrient calculator. I did this a few weeks ago. At 1.0 EC the profile is the following:
N: 90 ppm
P: 23 ppm
K: 88 ppm
Mg: 34 ppm
Ca: 129 ppm
S: 35 ppm

If i add 1 gr/gallon (~0.25 gr/l - i know you said 0.3 gr/l but i know the exact ppm for 0.25 gr/l) Epsom the solution will be:
Mg: 60 ppm
S: 69 ppm

The Ca is fucking high and the P is too low. It is confusing me. Or the calculator is wrong. Sorry ibreza, i know i am incomprehensible. I won't stop feeding Epsom. Thank you again ;)

Hey Snypie.

Glad to see you broke down your nutrient solution to real numbers. Now you have something concrete to work from. Great job! I think your CA is high and your N is slightly low. Canna runs a very strict 3:1 ratio for Ca/Mg. Try keeping your Ca and K at a 1/1 ratio. Good luck.


Here's the numbers H3ad ran for his coco and why. I think they are solid numbers to run. This should be a good comparison to your current nutrient solution.

Highyas guys...

After watching and reading and generally being impressed with the results you've all been getting with the coco medium, I've had to make the switch myself...

Being the rebel that I am...Not having coco specific nutes, and having a full supply of GH flora micro and bloom, I've been working at tailoring the 'Modified Lucas formula' I was using in pro-mix to suit the coco better...

The mix I have arrived at has reduced levels of K and P, and a slight reduction in total concentration, because I have been keeping the runoff to a minimum (only a few ounces of water come thru, just enough to let me know I'm completely saturated...

ln bloom which gives the nute profile:
N 97
P 60
K 105
Mg 41
S 27
Ca 97

adding 1 g/gal epsom salts to the solution changes the numbers for mg and s to:
Mg 67
S 61


Adjusting for the extra available potassium in the coco, the new formula puts me very close to the 'target ratio'... Phosphorous is a tad low, but I think there should be no worries there...

Nothing is too far along in flower right now, but I'll get some pics up a bit later.

I have also seen advantage in keeping the coco fairly wet, I'm guessing that the coco holds the nutes so well, that as moisture evaporates out, concentrations rise...
 

ibreza

New member
If you are feeding only bionova with RO at 1.0EC your calculations are wrong. bionova has 8% N so to reach 90ppm of N you need 90/8 = 11.25ml/l. let's round it to 11ml/l. bionova has 3%MgO which means 1.8%Mg so 11*1.8 = 19.8ppm of Mg. the profile should be:
N 88,00
P 28,38
K 109,56
Ca 89,76
Mg 19,80

By the way if you compare that to Canna coco, for 90 ppm of N:
N 87,40
P 27,36
K 45,79
Ca 85,50
Mg 27,36

the Ca:Mg ratio is a bit more balanced but it's not far from bionova. And Canna coco is meant to be used with tap water, adding Ca and Mg.

Adding 0.25g/l of epsom, you're at 50ppm of Mg. It should solve your Mg def and then you can go back to Ca:Mg of 3:1.

P is very low, It is barely enough in veg and during flowering you're going to have red stems all over your plants. Use phosphoric acid to lower your ph.
 

ibreza

New member
yep my mistake I was looking at my canna spreadsheet instead of the bionova :D
so it's not 50ppm but 45ppm of Mg
 

Snypie

Active member
Ok, that is great we can speak about nutrient profile. I made screenshots about it. I know if i mixed 0.8 ml/l BioNova A+B that gives me 490 ppm (0.78 EC) --> ~3 ml/gallon. And 1 ml/l (3.8 ml/gallon) exactly gives 600 ppm (1.2 EC).
The labels shows Ca as oxide form and the calculator wants just Ca. And this is also with Magnesium. I don't know the shift number, probably from here is the difference.

I also have Generaly Hydroponics nutes, but the European version called GHE and the label is a bit different. (There was a debate in the 3heads goes coco thread and nobody can't fgure out why are 3-4 different labelled product around the world) My micro is for soft water. I also took pictures from them so you can see the details (this is for 6/9). But on the GHE label also shows the oxide form (Cao, MgO and SO4 instead of just S). Can you help me figure out this thing?

I want to use one of them which is working in my situation.

Slide note: I can't use much phosphoric acid (PH down) in RO with nutes because the nute solution's PH rises after 1-2 days to 6.0-6.2 and just 1-2 drop of PH minus bring me down to 5.8. And i observed if i use just RO the PH in the substrate goes down. Today was the runoff PH just 5.6. And i observed also if i used 100 ppm base water (tap mixed with ro) i can use much more phosphoric acid (~15-20 drops instead of 1-2) and my runoff PH wasn't this low.

I also have BioNova PK 13/14 if this means and improves something.
13% P2O5
14% K2O
Weight: 1250 grams
Volume: 1000 ml

GHE Micro Soft Water 6 ml/gallon = ~ 1.6 ml/l


GHE Bloom 9 ml/gallon = 1.5 ml/l


BioNova Coco B at 600 ppm (1.2 EC)


BioNova Coco B at 500 ppm (1.0 EC)


BioNova Coco A at 600 ppm (1.2 EC)
 
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