Mg deficiency starts in the older fan leaves first.
I think your plants are growing rapidly and the leaves take some time to 'green up' after sprouting out. I love that look on my plants and my little ones are doing it now after being repotted just 3 days ago, well fed then put under a nice little LED I just got used last week.
You can see many of your upper fan leaves darkening and in a couple days they will be full green but with rapid growth the top bunch will always look lime green for a while. Higher light intensities green them up faster so maybe lower your light a bit or turn up the power if dimmed down.
I'm also seeing a hint of nute burn staring up on some of the older fans. Slightly raised leave edges with a bit of yellowing at the tips all along the sides. The green is very dark green which also indicates a good nute load so maybe go a little lighter on the nutes.
Check the height of the tops on a couple and I bet it's growing over an inch a day right now.
The purple could be low P but I'm not seeing any of the other symptoms for that. Many strains just do that. Too high Ca can block P and others as you see in the Ca pic.
Any help would be great
