Red Streaks in my stems

Hey guys this is my first post, and I wouldnt post unless something was bothering me about my little plant, These were clones and they came in a rock wool cube, so I just stuck the whole cube in the soil and sofar they have been doing fine .. but thats not what worries me.... its the fact that I just noticed these brown or red streaks in the stem between like the first nodes on the stem all the way up to my first set of leaves .. what could be causing this? any tips would be greatly appreciated !! Oh by the way the other clone is doing just fine, actually really well ... I might post some pics but im pretty paranoid about the law and fishing through the internet .. eh screw it as soon as i get a camera im postin my pics, but any advice would be greatly appreciated thanks !!

oh by the way, the strain ive got is Lifesaver crossed with NYC Diesel .. so i mean i dont think red or purple are part of the genetics, im leaning towards lack of nutes, any ideas?