Wats wrong with this

So I got this seedling a while back which was literally put in dirt from the sidewalk so I took it home and transplanted into ffof. Nearly pulled it out during transplant. Managed to survive And started doing well despite all the mistreatment in the beginning but then it started doing this . I gave some calmag and really weak vegetative nutrients but I guess even that was too much cause it got slight nute burns. Idk wat to do with this plant . This girl is literally a month old I have 2 week old girl bigger than her. She’s not getting taller but all the side branches r getting longer. I was never able to diagnose the faded spots in her there’s some in the new growth as well can someone please help idk if I should keep her or just toss her

I’m using RO water ph 6.2 temps r 75-83 in day 65-72 in night RH is around 35-45 range using hlg 300 v2 rspec at 25 inches