Seedling issues

I hope you don’t plan or watering those babies 👶 in 2 gallon pots till runoff, you will have to chuck em’ lol. Cheers 🍻

Looking at your diary tells me that you have major temperature swings of over 10 degrees with nighttime temps dropping down to 16 degrees C witch virtually stops the plants metabolism and then bake during the daytime under that nice looking LED grow light. 👍 Watering every other day religiously without proper wet/dry cycle or chronically under watering may/will compound the situation. You should have a gut feeling telling you what caused this as you know your grow environment more than anybody else on here. Follow it. Need to keep environment in check. Cheers 🍻

good quality coco? some are not as well buffered as others, then you end up with a k-tox or salinity issues. Give it time.. no reason not to. If others are healthy and no signs, less likely the coco... i still wouldn't delay feed in coco -- runoff will avoid buildup and it will help regain a healthy equillibrium of available nutrients (has to do with preperation of coco -- cation exchange sites will leech Ca and Mg while releasing K if not prepared correctly) as it leeches, it finds a new equilllibrium, you water to runoff to flush that away and replace with a healhty ratio.. rinse and repeat until it's at a happy medium for your plant. this is usually done before you plant, obviously... and solid brands do it well.

2 gallon pots in coco under 2 led grow lights. Temps get to 85 F and humidity up to 40% I spray the top of the medium every other day with pH 6.1 water. And the stems seem to be pretty purple