What’s up fellas. This is my first indoor grow. I have a 3x3 Gorilla Shorty extended to 5 feet tall. Mars Hydro FC-E4800 LED light. Pro-Mix BX and extra perlite for growing medium. I am running 9 plants in 3 gallon smart pots. 2 BF Orange Sherbert, 2 BF Dos Si Dos 33, 3 BF Strawberry Lemonade, and 2 Seedsman White Widow. All have sprouted and are about 42” under the light right now. Since I am running straight pro mix and perlite when should I begin adding nutrients?