Yellowing of leaves.

[addski]

Hi guys i have 4 Lemon kush x Chocolope cuttings in my wardrobe witch is a breeding project of me and my friend there 3/4 weeks into flower , i have only been getting this with the new blackstar i have a fair bit of experiance with growing in coco and with hps and never had any problems like this.
Im getting yellowing/browing off my fan leaves and i cant for the life of me work out what it is or fix it!!! (had same problem with crazy miss hyde , under the 240).

lets start with setup and feedings.....

240w uv blackstar
growing in Coco
temps constant 24.2 lights on and 21 lights out.
canna coco a+b
sensi cal/mag
buddahs tree 9/18
rhizotonic

There on 1.8ec and 5.8ph and run off ph is 6.7 last feed.

Here is some pics not great as there camera pics.



Like i said i have a fair bit of experience using these nutes and growing in Coco and have never experienced this , the only factor that is different in my grows is the LED.

Any help would be greatly appreciated

 

[Muddy]

It's not the lights. If you're feeding at 5.8 and getting run off of 6.7 your pH is way too high causing nutrient lockout. Need to get your pH in line and then you should be okay.

 

[addski]

It's not the lights. If you're feeding at 5.8 and getting run off of 6.7 your pH is way too high causing nutrient lockout. Need to get your pH in line and then you should be okay.

cheers for the reply muddy , but a runoff off around 6.4 - 6.8 is about normal for Coco or so i have read and always has been for my previous grows, i use small single trays to collect runoff and will always up the ph of runoff because of the build up there. its just a head scratcher.

I've never grown in soil so what runoff would you be for aiming in that? and how would you adjust? flush 10 times pot size of water?

 

[addski]

cheers for the reply muddy , but a runoff off around 6.4 - 6.8 is about normal for Coco or so i have read and always has been for my previous grows, i use small single trays to collect runoff and will always up the ph of runoff because of the build up there. its just a head scratcher.

I've never grown in soil so what runoff would you be for aiming in that? and how would you adjust? flush 10 times pot size of water?

Also I bring my seedlings and cutting on under a 125 cfl and they are perfect its only when they go under the blackstar it starts. if you go look at the craxy miss hyde journal i was doing you can see.

 

[Hugo]

Hi addski. The runoff pH is important as a matter of control. Getting a run-off of 6.8 it's not always good. I'll try to explain what muddy was saying.

The most important pH is on your soil. That's the one we are looking after all during the grow. The run-off pH, in whatever medium you are using will be an average of your intake pH and the soil pH. So, if you are feeding with 5,8 and run-off is 6,7 that means that the medium pH will be somewhere around 7,5. And that's really high for coco.

Coco coir should be maintained at around 6,5 pH. Take a read on this thread below. It will help you to know coco a bit better. You'll be able to adjust your pH easily with your waterings. I'd recommend a flush with 6,5 pH water, until runoff is 6,5!

http://www.420magazine.com/forums/hydroponic-gardening/76197-what-ph-do-you-use-coco.html

Hope I was able to lay it down for you. Anything else just ask.

Cheers

 

[Hugo]

In case you're getting a biased pH because of build up in trays, I advise you not to check the pH in the trays. Take the pot to a ledge and put a cup or a glass or anything clean for that matter to collect run off water. That way you'll know it's the best read you can have.

cheers for the reply muddy , but a runoff off around 6.4 - 6.8 is about normal for Coco or so i have read and always has been for my previous grows, i use small single trays to collect runoff and will always up the ph of runoff because of the build up there. its just a head scratcher.

I've never grown in soil so what runoff would you be for aiming in that? and how would you adjust? flush 10 times pot size of water?

 

[addski]

Thanks for the advice guys , i have now sorted the problem it is a buildup of calcium in the soil , witch in turn is blocking other nutes.
Its because i have been using the sensi cal/mag along with canna coco a+b witch is already very calcium rich.

So im going to cut the Sensi cal out of the mix and just run a lower ec mix that consists off...

5ml per gallon canna coco a+b
10m per gallon rhizotonic
2ml per gallon buddahs tree
with an extra 1.25g of Epsom salt for the mag boost.

This should give me an ec of around 1.2-1.4. and start to fight this deficiency. (im hoping)


The PH is pretty bang as the Canna coco is buffered to 6 - 6.5 so with a runoff of 6.7 with a cal buildup isnt that bad. I'll probley up my base ph to 6.

 

[addski]

Its just me getting heavy handed with the Sensi cal! as this is the first grow i have used it. I thought it was a must with LED's.

 

[Hugo]

I like to use Sensi cal/mag from time to time. When I do I use it just like if it was another grow nute. So if using fishmix and sensical I would use 0,5ml/L of fishmix and 1ml/L of sensical - that's half dose of each.

I'm glad you figured it out!

 

[addski]

I like to use Sensi cal/mag from time to time. When I do I use it just like if it was another grow nute. So if using fishmix and sensical I would use 0,5ml/L of fishmix and 1ml/L of sensical - that's half dose of each.

I'm glad you figured it out!

Cheers buddy. Was my own fault getting abit carefree with the nutes! lesson learned