Yellow veins since a week during vegging, LED

Hi all!


My latest attempt to grow under LED is a bigger succes than all the previous attempts but now I have a new issue:
My top leaves started to yellow from the veins. now 1 week later the yellowing is going more outward the leaves and lower and


smaller leaves are affected too now.


I think it is best to give an as accurate as possible description of the growing situation:


The grow is setup in my basement in a room next to my central heating unit (gas powered). In the basement there is a constant


temperature of 14°C (59°F).


My set up:
· The strain I use is the Northern Light feminized from Vision seeds and they are 8weeks old now (from seed);


· a secret jardin grow tent h1,8m (6ft), w0,9m (3ft), d0,9m (3ft);


· 90W LED grow light:SUNMEG:
Name: New 90W UFO LED Grow Light
Model: LZ-008
Specification from supplier: LEDs:45pcs 3W Epistar&Bridgelux, Lumens:3650Lm, Color:Red and Blue, Power:90W, Input voltage:AC86-


264V, Lighting Area:30Square meter, Height above the plant:2.5/3.0/3.5m, Wavelength:R:630nm;B:460nm, LEDs Ratio: 8(Red 630nm)/1


(Blue 460nm), Lifespan:50000H;
The lamp is poitioned 40cm (=16inch) above the plants.


· oscillating tower fan at the lowest fan speed so the leaves move just a little;


· I added 3 x 20W lCFLùs (2x cool, 1x warm).


· I use a 95W heating mat to compensate for the less heat by using LED.


· The temperature on top of the pots is 22°C (72°F).


· The temperature setting for the heating mat is 23°C (74°F). This temperature uis measured in the soil of 1 pot at its bottom.


Can there be a too high temperature for the roots???


· I use as a soil Biogreen grow mix (with perlite). This is already high dosed on nutrients. They claim up to 6 weeks in veg. I


repotted them into 25liter (=6,6 gallon pots) the 4th of Februari so there should be enough nutrients left I suppose.


· For watering I use tab water (EC0,6 & pH and warm it to 22°C (72°F) and add vinegar to adjust pH to 6,0. Since I repotted in


new soil, I have not added any nutrients as I am affraid to overnutriate as there are already nutrients in the soil. I water from


above and I water not very often. Approx. 3 times a week 1,4liter/plant (=0,37gallon).


.The humidity in the tent is between 50 and 80%. I use a hand mistifier.


What can I do to determine the cause?
Can it be a lack of nutrients or a lock out?
too much or too little watering?
pH?








I hope you guys can help me start up because I can not find someone that is able to help me on this because they don’t have


experience with LED grows.


Thanks for the effort!
RichHazed

I'm just a rookie but 59° seems a little low. That more than likely wouldn't be accountable for the discolorations though.

I'm sure one of the pros will help ya shortly! Good luck!!!

Sent from my SAMSUNG-SM-N900A using Rollitup mobile app

Hi Jartlow and thanks for replying,

The temperature in the tent is min 20°C and the root temp is even higher.
What I forgot to mention is that I'm using a 24/24 light cycle. i read that it doesn't hurt during vegging.

Greetz, Rich