HELP! Name that Deficiency

[Greenlivin]

You guys are my last hope. I’ve searched all over and cannot figure out what she’s trying to tell me. It’s yellowing on the veins, and only happening to a few leaves that are first on the branch(s). My best guess is a Magnesium deficiency? PH is between 6.2-6.8 when I water, and haven’t PH’d the soil. I will say I’ve had issues keeping the humidity high enough. It sits between 30-45% on average.

Growing 1g fabric pot w/ FFOF, with Mega Crop and Golden Bloom nutes. In 3rd week of flower.

 

[Willyd]

 

[Willyd]

to me looking at the pics and at the charts maybe nitrogen but im honestly just guessing i hope the chart helps

 

[Greenlivin]

Appreciate it man.

 

[FlyingDutchPaddy]

Hey Green,

going by the charts Willyd posted, i'm thinking Manganese (Mn), but...

It’s yellowing on the veins, and only happening to a few leaves that are first on the branch(s).

Willyd might be right with the N, considering that Mn is not mobile...