These are 4 autoflowers at 20 days from seed. I am noticing what appears to be N or mg Def. I have upped feed and foliar fed Epsom salts. Root drench had calmag canna a b at 3ml fed at 1-1.3ec
Appears to be either under or over watered. Check the stems. If the main stem is floppy, they're under watered. If the leaf steam is floppy, but the support stem is firm, then it's over watered