leave behaving strange

The rust on the midrib of the leaf would lead me to think it's phosphorous; none of the other nutrients fit that and also cause leaf distortion. Starting new seedlings in large fabric pots can be tricky, especially when there is a 6" lip from soil surface level, this creates a zone of high RH with little to no airflow. make sure there is at least some airflow on those pots; fabrics are not as "airy" as you think. Lights on the top 3"4 inch of soil quickly evaporate, and the tiny seedlings perform transpiration by pulling water through the medium, but only where they can reach. Right now, your roots are as small as your plant above ground, meaning they can only access water in the top 3,5,8 inches as the plant grows, most of the water will be pulled by gravity to the bottom of the pot, where it becomes entirely the responsibility of evaporation, not transpiration. Evaporation will not happen in ambient 72F 65+RH% if at all; it certainly won't be happening at night with lower temps = more moisture Having the pot fully saturated with water to 5-10% watering, in order to do so you need to have slightly warmer, slightly drier conditions to cover your ass with evaporation, the plant will suck up as much water as it can with transpiration during thee day, by having it slightly warmer and slightly drier, evaporation will ensure overwatering is a thing of the past, try and find the sweet spot where you water in just before lights on, and by night its just nice, not too wet, not too dry, rinse repeat. Water that just sinks to the bottom of tall, airy fabric pots with no airflow will stagnate quickly, causing a host of problems if not dealt with. Phosporous is the number 1 nutrient a seedling needs when it is first germinated, it's the milk of a mother's teet. Phosphorus availability and uptake by plants are significantly affected by soil aeration, meaning plants need an airy medium for optimal phosphorus uptake. Very easy to overwater these pots is what I'm saying, especially until you grasp evapotranspiration and how water cycles through plants. Cant be 100% sure but I tried!, hope it works out for you.

Perhaps early transplant stress or overwatering. The curl and pale color suggest roots aren’t thriving yet. Let the top inch dry out well between waterings and ease off on intensity if lights are close.

Hey there I don’t really see signs of ph issue when ever you can water enough there will be run off you can check the run off water ph but till then I’d just focus on the rh also maybe back down the light just a little bit to let the plant recover. The plant is going thru the stage where it hardens off. Sometimes if you let the plant recover for a day and leave the light super low like 50umols for a whole day then go back to that same light u had b4 the plant will bounce back also you maybe need to start watering a bit more so those roots will get all thru that soil ….