There this is the same plant it's my mother plant tht I have taken 5 clones from so far but wen I tested the run off water it's a super low of 5.5 n I ph whatever I feed or water in there b4 I do it to 6.8 and she has this yellowing on the edges and tips and dark green veins/centers I did a few pics outside so u can really c (same plant my mother plant jus dig. Angles) oh and I upped the cal-mag to about 6ml a gal. Jus 2 let any1 know so yea if sum1 cud touch down on y this mite be happening n cud let me no I wud greatly appreciate it
You should raise the PH of the soil. Whatever your soil PH is, it's got to be lower than 5.5 to bring a 6.8 solution down to 5.5. Try adding some dolomite lime and scraping into the soil.
BTW...I'm still catching up, so maybe this was answered and you're doing a great job and have come a long way since your first grow!
Like anything else, it takes a few times doing it before you get it and start getting good at it!
there ya go brother a proper welcome lol but yea if u see anything u think I can improve on let me know constructive criticism is always welcome here. Anyway glad 2 have u around 
