My girls are yellowing at the bottom and dying off

[Trillionz]

Have 6 northern lights x bigbud in 5 gallon smart pots.
Nutes: gobox
Lights: started with a t5 4ft 8 bulbs
Switch to 2 600w leds two days ago
Soil: m3
The plants are 6 weeks old

 

[Waira]

Trillions- ...I need some pics in normal lighting, mate,.. that color spec' is very bad for diagnosis,...true color is critical for this,... That said, at 6 weeks, it's not uncommon for some of these lower leaves to start getting tapped into for their nute's, and as you approach harvest, more and more fan leaves will begin to shut down,... Also, Ca-Mg defc. issue is common about this time as well,.. get me those pics please, so i can get a better idea what's going on,... :Sharing One:

 

[Trillionz]

Here you go Waira

 

[Waira]

..thanks bud! That's looking like Mg defc., a little different in appearance than usual, probably because some leaves are starting to tapped into as part of the natural cycle,...don't sweat a few leaves croaking out.... I see some very nice color starting! :Cool bud: So, what do you have for Mg supplements? A dedicated Ca-Mg is best, but epsom salts (MgSO4) are great too; dose at 1 level tsp/qt soil drench,... it'll slow the yellowing down, but remember, some of this is perfectly normal as the plant reaches the end, so don't be alarmed if, soon, other lower leaves start to pale out....as long as it's not happening to lots of them in a short time, which so far it's not, you're looking fine! Is this the WoS cross? I hear very good reviews about this one! :drool:

 

[namvet25]

Right on brother Waira.:Sharing One:

 

[Trillionz]

Thank you. I'm using a go box