Healthy looking plants man. Your day time temps are a little cool right now. Cannabis plants love heat and humidity the buds do not like it lol. Your growth will be slightly slower with temps in the low to mid 70s. Veg and early flower aim for mid to low 80s and less than 10 degree difference with lights off. Also for 310W lights try and get them closer. Do you have a PAR meter or thermal gun to read temps ? They will help you a lot to get the most outta your lights. Keep up the good work man