ok so Iv seen the answer to this question all over the place,and its varried it seems,I am starting up an led grow in the next few days,just put everything together,will be using a 90watt led ufo light, "usa made"....in a GL40 tent,only thing Im not sure of is the distance I should have the light away from the tops of plants? 12" 6"??? someone please help! lol...anyone using or had sucess using 90 ufo type lights,how far was ur lights away from plants? thanks for any help!