you should never add nutes to seedlihngs...period.

Once they have 4-5 alternating nodes, you can start with a 50% solution, prcdedding with full veg nutes the following week...I usually do not add any nutes for 2-3 weeks, depending on pace of seedling. then i veg for 2-4 weeks, depending on how bad I need weed...

drainage is key...another big tip: when I start seedlings, I spritz the medium they are in with water/w Superthrive 2-3 drops per liter squirt bottle...Spritz'em nice and wet, 2-3 times a day. hope this helps, lw