Coco deficiencies in flowering, CalMag?

[Weisskraut]

Hey there,

I´m growing in Coco with drip irrigation. Since flowering week 3 I am having issues with nutrient deficiencies which is getting worse. I feed them with TA Tripart nutrients, Ph 6.0 and EC 2.0
0.4 Ec-points are coming from Mono Cal and Mono Mag.
It is a closed loop system with 1200ppm co2 and 1000ppfd.

Do you have any ideas? I thought it might be CalMag deficiencies and that´s why added CalMag but it really doesn´t solve the problem.

Thanks

 

[Bdubs]

It is hard to say. I would guess phosphorus deficiency due to nutrient lockout.

 

[Imzzaudae]

Did you buffer the Coco before planting? Sounds to me like your Coco is holding onto calcium.

 

[m8ty]

It can't be a deficiency with 2 ec worth of nutrients though... Have you checked the run off ec?

 

[Northdank67]

add 0.2ec calcium and see if that fixes it. i run about 0.5ec of calcium alone in flower

 

[Northdank67]

but to me this looks like a N and a possible Ca defiency

 

[hoobastank_enthusiast]

First thing to ask is where is it starting, at the bottom with older, larger fans or up top with newer growth. Looks like the bottom with old growth which implies it's a mobile nutrient which generally means one of N/P/K/Ca/Mg.

 

[Weisskraut]

Just measured Runoff. Ph is 5,5 and EC 2.5.
Older leaves Turn yellow First.
Should I keep adding CalMag or May I risk a Phosphorus Lockout?

 

[MrCannabisExplains]

Hey Weisskraut!

Do you measure your runoff consistently? You don't want to base your decisions off of random checks, as you can get outliers that may not properly reflect what's normally going on in your root zone.

Next, are you really just in week 3??
Those are some big buds for that age! This could be the root of your problem, running CO2, a good PPFD... you could just be using all your nutrients up! Again, don't want to base too much on your SINGLE runoff test, but 0.5EC higher than what you're feeding CAN show that there isn't much build up happening in the media, even with evaporation. What you're feeding is being absorbed by the plant.

Your issue looks like basic N def, with much of your lower, and even middle fan leaves going chlorotic(yellowing) pretty uniformly across the blades. She just looks hungry.

 

[Weisskraut]

Picture is from flowering day 31. But deficiencies started in week 2/3.
Saw some Tip Burns when I was feeding with EC 2.6 so i thought it might be a lockout.
You think I should rise substrate EC again?
Thank's from germany

 

[Weisskraut]

Think I will Switch to 50/50 Coco soil Mix next time. Hope that will reduce Problems with my nutrients

 

[Northdank67]

Think I will Switch to 50/50 Coco soil Mix next time. Hope that will reduce Problems with my nutrients

I think you don't have a problem with the media you grow in but the feed you're giving your plants.
maybe do a bit more research on what the plants need throughout their whole growth cycle?

 

[hoobastank_enthusiast]

mixing coco and soil(less) together is an awful combination, a really great way to get all of the downsides and none of the benefits