magnesium deficiency??

So my girls started to turn purple within the past couple days. Their in FFOF that was cooked with dr earth 4-4-4 and EWC for 3 weeks. I transplated them into that dirt 5 days ago and they only get straight water ph or around 7. Temps are from 63-76. Under a 630w led 40in 50% power.Any help would be appreciated!

I see nothing but a healthy little plant

I see what you’re talking about. If those areas start lightening you might apply a foliar spray of Epsom salts.

Here's some better pics. Seems like it's starting from the bottom and working it's way up but mostly just the top sideof the stems. Maybe their not used to the light? Read somewhere that it could be like a sunblock because of the light.They were under a 135w hlg bspec but when I transplanted I put them under the geekbeast at 50%I'm actually planning on hitting em with a epsom/protekt foliar tomorrow or the next.