Stem discoloration? 2 weeks in flowering

CaliGrowin

Active Member
Hey guys, I'd try & diagnose this a little better myself but I'm colorblind & not too confident with my colors haha... Anyways, the plant is just about 2 weeks into flowering now, & there's this odd stripe going down the leaves' stem underneath and the same color on the top getting lighter as it goes back towards the main stem. I'm not sure if the stripe was there before switching to 12/12 or not... I don't have much technical info for you guys sorry, just let me know if you can tell anything by these photos. If you need anymore info let me know...

Also, I haven't given it any nutes in any form. It's growing in some OSH pre-fertilized soil, but I've flushed it a few times so I'm not sure how fertilized it is. These conditions lead me to believe it could be either that I've flushed all the nutes out of the soil (assuming it even had a good mix in the beginning), or it has too much of some nutes(not sure how likely that is).

Thanks in advance!!

Here's some pics:
 
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