Seedling help please

[stephyyy]

Hi friends!
Need some advice with my seedlings. These AK-47 seedlings are almost 3 weeks old and some have started yellowing and curling at the tips of the leaves like in the pic. I haven’t started nutes yet cuz I usually wait til third set of leaves but I’m thinking the issue is either nitrogen or under watering. Advice please??

 

[BostonBuds]

What is the soil, the potting soil I use is 0.05-0.0-0.0 so I start adding light nutes around week 2.

 

[stephyyy]

What is the soil, the potting soil I use is 0.05-0.0-0.0 so I start adding light nutes around week 2.

Ok I added some light nutes this morning, I use organic seedling soil so I feel like these seedlings are hungry now