Brown spots on seedlings? Also what should my ppms/feed schedule be at these stages?

[YBGTA]

So I have like 5 3.5 ish gal 5 gal buckets running med airstones with 5ml or 1tsp of each nute from GH Trio with hydrogaurd at 4ml each bucket and I've been struggling with humidity but have gotten a vaporizer so it's risen a bit, but my one Plat "bello y dulce" has its first true leaves turning lim3 green with brown is slors that started black and grew to a brown spot someone mentioned a p deficiency? Could calimagic fix this?,it's been half way Into this feed week and I'll add some calimagic in next feed(week )


Ps do they look stunted? Its been 3 and a half weeks since transplant, I have at least 1 airstone for every bucket

 

[Newty]

Just a heads up, you posted this in the classified section of the forum where people buy and sell things. If you post in one of the normal forms, you might get better help.

 

[YBGTA]

Just a heads up, you posted this in the classified section of the forum where people buy and sell things. If you post in one of the normal forms, you might get better help.

Thank you, little confusing lol.