Plant problems please help

I have been growing this plant for about a month now and the past week or so the newer sets of leaves are turning yellow between the veins. Some of the leaves are slowly starting to curl inwards, the plants growth hasn't been stunted but I am beginning to become concerned, could someone please help me diagnose this plant this is my first grow btw


[img=http://s9.postimg.org/61omjwi8b/image.jpg]

https://www.rollitup.org/marijuana-plant-problems/800708-having-problems-your-plants-most.html

Literally just found this, hope it helps.

Might be calcium deficiency. Maybe not either. pH of your soil is what I would be checking.

boron,or salt build

@AimAim

Ill check the pH of the soil tonight, if all is good with the pH, how would i test for calcium deficiency? cheers

@tyke1973

How would i test for these being the problem, Thanks

@frizzlegooch

Thanks bro, thats defo narrowed it down to a few potential problems, cheers

Your welcome buddy