Yellowing… why, N, maybe Mag….😭

Looks like your asking too much from your plant.. Cake them in nutes and light is only half the story. Roots, environmental factors and co2 adds another few problems to get over.. You are trying to force feed a fat pig...

Doubt it has any issues to do with Nitrogen in a deficiency especially if your using Gaia Green, that stuff almost always gives me N tox. Your week 6 looks like it has to much N and week 7 is showing the discoloration. Leaning towards light and maybe a small issue with Mg but not the main cause. I read your giving them 24/0 lighting to get a good DLI.... you can get a "good" DLI from less hours on its all about intensity over time. Eg. you can have a DLI of 40 over 12hrs or 24hrs and its the same thing. I would be dropping your plants down to a 18/6 schedule or even a 16/8 with around 35-40 DLI. your light is 600W and can totally handle it. the plants can't utilize much more then this without supplemental CO2, this number is based off of research from DR. Bruce Bugbee. A cannabis researcher from the Utah State University, they know their shit, more then most of us on this site. You quote PPFD in your diary, if your using photone app to calculate this, know its not accurate but it is replaceable. eg. its not the true PPF but it will show you the same number even if its not true. Better to go off of some of the manufactures light maps and then adjust from there based on the growth. To tight, to much light, to loose not enough. Your earlier weeks were talking about node spacing being to tight. Sign of to much light. Use that dim function to its full potential. Mg does not need to be high dose either. Can sprinkle in a bit of epsom salts if need be. eg magnesium sulfate. When I have used Gaia in the past I find it needs a bit of a Mg boost every few weeks. and with out it. my plants look a bit pale. Its not a perfect product but it does well for what it is. but fix your photoperiod eg 24/0 as thats not helpng and plants need downtime.