What is happening to my young plants?

growdiaries.com/diaries/250925-fast-buds-banana-purple-punch-auto-grow-journal-by-cannbellfarms is this the diary they are in?? Should link it to the question so other can see it. The growth between week 1 and 2 seems good. Maybe they just need more time? I don't think your coir looks to dry in the small pots but if it is, give it some love. water all of it and get a bit of runoff. With coir you always want to be giving it some nutrients and CaMg as its void of nutrients and the coir has a tendency of releasing Na and K if its not buffered correctly. If you using a lower grade of coir a mini flush with some CaMg would be needed then follow though with a week feeding. Just ensure the medium is not getting overly saturated and waterlogged. I would also only do this is the coir was of lesser quality. Also this... the light is recommended to be at 20% for seedling not 50% and the hang height is 16" throughout the entire grow. Maybe lower its intensity to the min and watch the plant. To much stretch bit more light. no stretch at all between nodes. less light. https://www.spider-farmer.com/wp-content/uploads/2024/10/2024-Newest-Version-Spider-Farmer-Dimmable-Foldable-3000K-5000K-Full-Spectrum-800W-Led-Grow-Light-G-Series-G8600_A_PC_2.jpg.webp

Your coco looks incredibly dry............try watering until you get some run off and then see if they perk up.

70 rh% is alot of moisture for 72f, hard environment to breathe, hard environment to photosynthesize at low temps. Plastic pot prevents oxygen action of rootzones also.

Hi, Which substrate are you using? All Mix or Light Mix? What is your lamp setting in % and how far is the lamp hanging from the plants? Are you already using fertilizer? How much water do you give the plants? What is the pH value of the water? Unfortunately, there are many questions that need to be answered first. I think it’s light stress. Reduce the light intensity a bit and give your plant some CalMag.

It appears that maybe you’ve given them too much nutrients too soon. Your light DLI on a young seedling need only be around 15-20 for the first couple of weeks or maybe 20% power and 24-30” off the plants. Some are more sensitive than others. Your VPD plays a big part in a young plants health as well. You have several grows so this may fall into that category. Always check the PH to ensure it is correct, for the medium you’re using. If it’s not right, you’re guessing at what is wrong.