ILGM Heavy Hitters First Time Grower

Aug 6, noticed a few things this week 1)yellowing around a few of the leaf edges, on the blue dream, and the MKU, and a few mangled leaves..it seems minor, affecting only a few of the fan leaves and buds are forming up so im not too worried, just curious what it is. 2) Stems deep red, I've been told this could possibly be genetics, cold night temps, or root bound. the two showing these signs are likely root bound. 3)Pest check was nil...I thoroughly inspected the entire grow space and found nothing, no signs of pests anywhere. I suspect the two demonstrating these problems are root bound and thus experiencing some nutrient issues at this critical stage..fingers crossed that the problems don't worsen, for now my plan is to add 1/4 tsp/gal Cal Mag to during normal waterings as a top off approach. If the problem worsens, I may flush each with 10 gallons of prepared nutrient solution to reestablish a proper level and flush any excess salts out, hopefully stabilising any potential ph problems in the process. will update in a few days..