Jaunissement ??

Well its normal to get different phenotypes of plants even in the same seedpack. Which breeder are you working with? For me it first looked almost like a early stage nutrient lockout but according to the other guys here you might just have to give them a little bit of extra love in form of fertilization. However symptoms of a lockout and a under-fertilization are very similar. In the end the plant doesn't get enough nutrients. If you have the feeling you gave them more than enough fertilizer it might be a lockout and you need to flush them however if I would work with mineral fertilizer from now on to give the plant instant and easy access to the nutrients.

Give the yellow one 500-700ppm of veg fert with some run off That will get it better in a few weeks

Si tu n’a pas de problème d’eau stagnante dans la coupelle de ton pot, je pencherais pour un manque d’engrais. Bon courage !

It Needs fore food comparedvto the other One plants are like people we all eat different

Hey bro, just guessing here since there’s no diary, but looks like that yellowing one’s running out of nutrients early, probably nitrogen deficiency mid-bloom. Could also be light root stress or poor uptake if the mix is too airy sand + potting soil ain’t always the most stable. It’s not too late. She’s still pushing pistils and stacking. You won’t turn the leaves green again, but you can slow down the fade and help her finish strong. Give her a light balanced feed with a bit more nitrogen, not just PK. Water nice and slow, make sure she’s actually absorbing, could be dry pockets or uneven soak. If you can, check pH of runoff just to rule that out. And yeah, sometimes two “identical” plants just don’t act the same. Genetics are like that. The darker one just got the better draw this round. Good luck 🤞🍀♥️