Well get the veg room clean of mites and keep it that way. My veg room is like fort knox, the most secure and sterile room of all since it houses mothers. If the veg area has mites at all then you will constantly have issues. If it's sealed up from outside then the only way mites are coming in is on you, your buddies, pets, plants. So nobody need be in there but you and like I mentioned don't go in there if you've been outside and could have mites on your clothes. I keep a pair of house shoes for my grow room only, don't wear shoes I have been outside doing yard work in. lol
Back in 2012 / 2013 I was consulting for a commercial grow out here in Colorado, they were stubborn as fuck and rarely listened to my advice. They never got a crop out of their grow, in what ended up being about 18 months of operation before they went bankrupt. I warned them about being clean. The owner had a fella that was poor and would do any odd job cheap, dude rode around on a moped and would even work for a sack lol. He would be at the owners home running a weed eater, then roll into work go into the grow room and start watering plants with clothes still plastered with weed clippings. lol Yeah they had mites, duh.
I also warned them about growing bag seeds, hermies and all that, bag seed is there for a reason. Well the owner had a shoe box collection of all the bag seeds he had saved up over the years, some really good strains he said, thousands of beans. Well they shotgunned a shit ton of them, it was 700 some odd plants they vegged, filled up a flowering room with them and were only watching for the typical male balls to cull males. One day they asked me, what are all these little flower looking things laying in our trays below the plants? I went and looked, sure enough, banana peels everywhere from a shit ton of bananas popping, yellow dust everywhere. At least 50% of the plants had busted bananas. I showed them the bananas still on the plants, the piles of pollen laying on the fan leaves and sugar leaves of the now 5 week flowered plants... Whole room full of seeds, not a small room either. Fuckers were trying to sell the seeds lol Like seriously, sell hermie seeds to folks? Dick move. Between mites, hermies/bag seed and powdery mildew they never got a run out of their massive grow. Fuckers coulda made a fortune if they had only listened to my advice. Everything I told them would go wrong did.