Seedlings in Coco Going Downhill Fast!

[low_and_slow]

Man...what's that like 30 gallons of fertilizer down the drain? Yikes.

I'd avoid any supplements beyond the base nutrient lineup. If you're seeing deficiencies, play with your pH before you add a variable. Just my $.02

 

[idiopathic neuropathy]

I was thinking a crap Coco as well, my grow in Coco I just started is very similar to everything you do but I used Canna Coco Pro Plus and Canna Start for feed in the very beginning.
I'm going to disagree with 6.5ph being a problematic run off figure in Coco, maybe it is for soil but most run off I tested during my first grow was always around 6.5 or higher even though I always water with 5.8 - 6.0 ph

I've been growing in coco for ~3years.
I have ran experimental tests with 2 coco brands, namely Sta-green from Lowes, and Black Gold, both are not buffered but claimed to be rinsed. I have used them straight out of the bag. Also I have rinsed and strained the small particles out, then ph'd to 5.8. Then I have tried another batch rinsed, phd 5.8 buffered with calmag. I have tried another batch by rinsing, phd 5.8, soaking in calmag twice for 24 hrs. According to Dr. Cocoforcannabis. I have even reused coco and performed the rinsing and buffering according to Dr. Cocofocannabis.

My results----all methods showed some minor degree of calcium and or magnesium deficiencies. It's baffling to me.

I decided to research/read on the internet everything I could possibly find on cococoir. My conclusion-according to the articles-there are so many variables at play as has also been reported by the infirmary experts here on AFN, eg. One nutrient will lock out the other or other environmental controls will effect the plant.
Therefore, it is difficult to determine what is actually the true cause(s) when the plant is reflecting toxicity or deficiencies.

My findings on testing runoff---ec can be very valuable to see if the plant is uptaking nutrients. However, Ph runoff is of little use. I have had what I consider successful grows where ph runoff is consistently in the range of 6.4-6.8 throughout the grow.

 

[LuGoo]

Thanks for chiming in @idiopathic neuropathy! So do you remedy by adding calmag? If so, what's your regimen?

I heard the Coco Doc on a podcast and he mentioned coco eats tons of calmag, and continues to eat more and more as it breaks down. This is why he recommends adding calmag throughout the grow. He also suggests you could first try to remedy with foliar spray so the coco can't get to it, then if needed, add to your fertigation solution too.

 

[idiopathic neuropathy]

So do you remedy by adding calmag? If so, what's your regimen?

Short answer is yes, I have always had to add cal/mag. With GH flora trio, from week 2 dependent on genetics and if I pretreated the coco, "generally" speaking 1 ml/gallon and by week 4 up to 3ml/gallon until ~3 weeks prior to harvest where I no longer I have to add calmag----this is all based on "reading the leaves". I have tried foliar spraying, but this doesn't solve the problem(s) where it lies which is in the roots. Therfore, more often than not i don't foliar, because i have learned to watch those leaves to respond with applying calmag with my nutrients which is more effective. I am constantly fine tuning the nutrients to what I am seeing in the plant. I just wish the plant could tell me earlier what it needed....lol. I have tried dr. Coco's recommendations with lackluster results----they did not work for me.

 

[LuGoo]

I think my ladies are far too big to be feeding only 400-500EC, so I want to ramp them up. However, several of them of very slight yellowing on established leaf tips, and one has significant yellow tips on NEW growth coming in (pic).

In my experience, this means too much EC, but I imagine there's no way that's possible at these levels. Can it also mean not enough nutrition?

 

[LuGoo]

Any opinions on this guys?

Can nute burn symptoms actually indicate LACK of nutrients? I wonder how symptoms first show up if you entirely cut off nutrients... ?

It's starting to show up on other plants. They are solidly in veg and I assume underfed... or so I thought.

 

[elcoloan]

Full pics of the plants would be nice to see how big they are now.
I'd insist you do a pH an EC slurry test just to make sure what it is that your coco comes like.
If you skip this, at least try constantly measuring your runoff EC and if it's lower than the EC that you put in, you are probably right and need to increase nutes a bit and wait a week to see what happens after this increase. If runoff EC is equal make sure input pH is in proper range. And if runoff EC is higher than input, I would reduce input EC.
And also try to set your input pH at 6.0-6.2 and don't bother with the runoff pH... give it a try, it works for several people in coco and MegaCrop... in my coco if I go below 6.0 too long I get Mg def symptoms in lower leafs and plants get a general light green, to avoid is my input pH is usually in the 6.1-6.3 range.