400w hps gets hot in a closed closet.. you really should work out some ventialtion to keep the heat from the light from cooking your plants...you can fit as many plants as you can cram in there. I suggest buying 5" pots and filling it all with clones . fit as many as you can fit in the space.
cold + hot = warm... seems like its the only choice lol.. do it upin my country 24 hours a day the air conditioner is working in my room to keep temp in 18 to 22 c !!
because in my country out side temp is around 40 to 48 c !!
so i can put a fan beside the air conditioner and blow the air to my closet ( 18 degrees air )
it will work ?