you can laugh but it you wish not to spray your plants with chems then buy some
aphids introduce them to your grow them after one day ladybirds then spray the fuck out of your grow with washing up liquid in water
Wait,, why aphids? Wont they will just munch on the plants,, and then you would have two pests to deal with.
also i found you need atleast 2-3 'doses' of ladybirds to get mites under control, and even then i dont think they will get them all and are not the best form of biological control for spidermites. When ever i have used them i have put them out just after lights out and of the 50 mayb 5-10 at most are there the next day, as they kamikaze at the HID. I have had good exp. with persimilis, but you have to sprinkle them on each plant. And once again two doses just to be sure, and if you have neemed or sprayed with owt systemic they dont do very well,
i would have to look it up as i cant remeber exactly but im sure the persimilis needs over 12hrs light to be actove otherwise they hibernate so if your in flower you would need a different species.
I have also used green lace wings, not for spidermites but for thrips but they eat most veg/sap eating bugs, they also fly about to lay eggs. They do need some care though, quite alot, the adults need to feed on nectar/pollen/sticky honey-dew so you need somthing, i used 'nectar' water in a small glass,
sgit sorry im starting to go on, anyhow take it easy and best o luck.