I initially noticed that one of the plants looked different than the others, and was excited at the possibility that one of the Harlequin seeds I thought I killed ended up taking. It was still difficult for me to notice at this time, as I'm still new to this, but it became more and more obvious as time went on. I took a guess, initially, during the seedling stage, as to which was which, and I picked right, because I wanted the Harlequin to do better than the NL, as the strains I initially picked are for medicinal purposes more so than recreation.
I used a similar method to when I was growing hops to grow these. for the Harelquin, I used a self wicking bucket system for all plants. 3 gallon soils bucket for the Northern Lights and a 5 gallon soil for the Harlequin. My reasoning was that I wanted more space and food for the more "important" of the strains. All the plants were doing well, BUT I started to get fungus gnats, so I picked up some Neem Oil and sticky traps to help curtail them. A big con of using soil. Probably won't do soil again in the future.
Having 3 plants in my small tent eventually became an issue, but I'll discuss that more on a later week.