young plants getting a lil yellow

hello, i have a question about my plants, they are about 3 weeks old, about 6 inches tall and looking okay just a lil slow cuz i want to avoid nute burn. been using my 3 part system at 1/4 strength for about a week, water only previous to that. all 3 look good abd healthy xcept for 1 that has yellow leaf tips, no curling just a lil yellow, im thinking nitro def. so im thinking more nutes? or is this nute burn, i ead the FAQ i think i have an idea but could use other opinions.


ps. no pics atm, hoping to get somthing like that for xmas ><

bumppppppp

bummmmmmmmpppppppppp

yep. like you said its probly a nitrogen deficiency.

Id get pictures before you start getting diagnostics without visuals.