What's the best nutrients I can give my og st...

Looks like you have the good genetics part down. You should be thinking about up sizing their pot soon so you don't stunt them by cramping their roots. Since growing a great root system is the next part you should add some beneficial bacteria and mycos to your soil to breakdown the fertilizer to allow your roots to use it more efficiently. Advanced nutrients Voodoo juice and Piranha are great products. Using AN Sensi Grow PH perfect A & B during veg and Sensi Bloom Ph perfect A & B along with Big Bud for bloom is the best way to go. You can finish up with AN Overdrive to bulk up those buds in the end. With the genetics you have you'll have some sticky danky goodness. You should check out their nutrient line up on their site and you can use their nutrient calculator to print out a custom feeding schedule for your grow based on your base nutrients and experience level. You can keep it simple or go all mad scientist on us. Good luck