Those are looking great dit. I put my hashberry into flower at about 20-22 inches. I have plenty of head room, about 10-11ft. The temp here drops rapidly aswell as I am seeing snow as we speak. At night I have no way to heat my grow room without adding light, the only heater I have gives off light. I dont need the extra heat, its just not as warm and humid as I would like it to be over night.