Komar85answered grow question 4 years ago Overwatered.
Too much light
. Are u use full power ?
Start with 25% (seedling)
Early veg 50%
Start flower and all stretch 75% power
From week flower 4 -5 full power 100% (8-9 week strains) from week flower 6-7 ( 10 + weeks strains)
Check distance with lamp manual
Also looks like nutrient burnt . If growing in soil most soils are charged for at least 3 weeks so u shouldn’t use nutrient at all . Check soil description. At this stage plant need around 150-200 ml and should least for a week . U need moisture not flooding environment. Overwatering cause that little hairs on roots start dying
I use Light mix ( Biobizz) for seedlings , clones and early veg
All mix (plagron or Biobizz depend what on stock) soil charged for 3 weeks only water
I hope this gonna help
Happy growing