Fan leaves getting lime green blotches

[BunkerBSMNT]

Hey all. So since this is my first grow in forever and first time with LED or coco I was wondering if I could get some help identifying what this is. I'm getting lime green splotchy patches on some of my fan leaves. The plats look healthy otherwise. Anyone have an idea what this could be?


Grow Stats

Strains:
Purple Urckle
Pineapple Express

Lighting
450W LED (4X 50W cree COBS + 200W array of proper spectrums including IR and UV)

Ventilation
350CFM (6" Vortex S-Line Fan)

Grow Room Specs

11'X11' Cement room in basement.
5'X5' area for actual plants.

Lights on
Temp is 78F-80F
Humidity
50-58%

Lights off
Temp 72-74F
Humidity 55%

Grow Medium
100% Canna Coco (5 Gallon Rhizo Bags)

Nutrients (I use Reverse Osmosis water)
In order of addition:
2.5ml per 10L of Armour Si (GH)
13ml per 10L of CalMag+ (Botanicare)
25ml per 10L Canna Coco A
25ml per 10L Canna Coco B

PH 5.5-5.8 (after nutrients sit over night and sometimes a 0.2-0.4 correction made with PH down)
EC 1.6

Plants are currently in 2nd day of second week after switching to 12/12. Drain to waste (backyard plants). They are watered once a day at lights on with about 2L each which gives me about 25% runoff. Foliar sprayed once a day just before lights off .

 

[Enforcer]

Those are from the pH being a little low. I get the best result around 6.1-6.2. When I was down at 5.6-5.8 I got leaf coloring like that.

 

[BunkerBSMNT]

Thanks I’ll adjust the feed water a little.

 

[Jimster]

You are in the beginning stages of nutrient lockout. With your Ph that low, it interferes with the plant's ability to use some nutrients, possibly magnesium. A foliar feeding of Cal-Mag should help until you get the soil fixed up. The foliar application bypasses the roots, which is where the lockout occurs.

 

[BunkerBSMNT]

You are in the beginning stages of nutrient lockout. With your Ph that low, it interferes with the plant's ability to use some nutrients, possibly magnesium. A foliar feeding of Cal-Mag should help until you get the soil fixed up. The foliar application bypasses the roots, which is where the lockout occurs.

Thanks for the tip. I’ll up the feed ph and water to more run off.