Thats way to early to start feeding Nitrogen. You need to consider that the soil you are using is already packed with nutrients. Consider checking the grow table from your soil manufacturer.
What components are useful in the seedling stage? Rhizo / Root Juice
And my soil is coco coir with perlite
Come again? Which Nutrients are you using atm? I would be extremely careful with using the Grow Nutrients at this early of a stage. If you use them and really want to keep using the this early make sure to use a low dose of ca. 1/3 of the recommended dose and most importantly water enough meaning you have runoff! So you water untill a little water starts coming out of the pot, otherwise you will start to build up salts in the bottom of your pot.
Which soil are you using and what grow week is it
boothohn is a Spammer, report him!