pyrethrum spray every 5-6 days for 3 weeks to kill all aspects of there growing cycle.:dance: :dance: Pyrethrum is photo sensitive so the light will disapate the stuff. The problem with mites they come from every where and anywhere. Using a intake fan keeps the room at a positive pressure so they have a bitch of a time getting in. I use a wooden frame with a pantiehose over it , then a normal airfilter , THEN a hepa filter. (the little bastards not make)
Here is a simple box made of normal 11-1/2 shelving and some strips of pine. You need to put extra strips on the sides to make it 12-1/4 that way you can use simple 12 x24 inch filters. make a frame out of 1/2 in lumber to streach the panty hose over. I change the filters out every crop. The only time I mites is when somebody brings them in.