Thanks. The last few feedings they were getting Sweet 25ml/gal, Purple Maxx 1tsp/gal, CalMag 10ml/gal, Diamond Nectar 8ml/gal, and Hygrozyme 8ml/gal. Now I'm switching things up. Normally I'd be giving them a few feedings of Gravity right now but I think somebody swiped my gravity because the liter I had of it is gone. It really sucks because Gravity just got banned in California so now I have to go out of state and stock up. Since I don't have Gravity I'm going to finish them off with Super Bud Blaster at 1tsp per 5 gallons along with Sweet, CalMag, Hygrozyme, and Diamond Nectar.
Sour Grapes gets purple hues towards the very end. If you want the more intense colors I'm getting you'll have to add Purple Maxx to your feeding regimen. Regarding your AK that's stunted since day 26, what are you feeding them and what are the PPM's. They don't look burnt but might be having lockout if your PPM's are too high. Try adding Diamond Nectar to your nutes. It will help with your root zone and help nutrient uptake. Carbs are good for bulking up your plant. I get the best results from Sweet and Carbo Load. If you're on a budget you can also use molasses. One thing I've noticed with molasses and Carbo Load is that you get a frothy slimy buildup in your reservoir with them. You don't get that with Sweet.
Here's the link to my Sour Grapes grow journal. Four 1K lights. Two Sour Grapes and two Space Queen:
https://www.rollitup.org/grow-journals/489458-4000-watt-sour-grapes-space.html
Here's a link to another grow I'm doing. Only one 1K light, 16 Green Cush plants:
https://www.rollitup.org/grow-journals/490721-1k-watt-green-cush-grow.html#post6692375