defoliation is ONLY necessary when leaves are stacked on each other preventing airflow or large leaves that block a huge amount of light for the rest of the plant. You need to keep it to a minimum because defoliation besides the 2 reasons mentioned above is only decreasing yield. Wait till the plant stopped stretching because this will be her final shape. Then study the plant and loom what leaves can cause problems due the reasons mentioned above and defoliate them NOT more! Happy new year buddy and enjoy this grow, your plants look great!