thinking about doing 4 tables with 4x4 trays each under 400w maybe 600. differnt strain under each light. dont really have to close the room off because i never have guest so could i open the window and the room door for ventilation or do i have to buy some stuff like i see in alot of pics to pull air from outside. would a fan work in the window and let the door release old air to the rest of the house