hmm, well if theres no nutes being given, maybe u should consider it? (this is just an assumption, dont jump to conclusion but look into it) i know that seedlings should be started in unferted mix (which uve done i see) but ass they mature into an adult and really get into veg, they need those nutrients, perhaps that could be it but again, just an assumption.

that might not be a bad idea to use ferts the next day, this way the plant has water and so wont be soo thirsty and suck up too much nutrients at once.as well, by assumption (so i like to hypothesize a bit) maybe the water already in the plant might make the flow of nutrients smoother and less shocking to the plant. so as long as ure starting on low dossage (i started at 1 4th of recomended, and worked my way up) then u should be ok to try it, just not heavy watering (dont needa drown the fellers)