There is one way to kill them eggs and all in one shot. Forbid 4f. Forbid 4f is so strong you dont even have to spray the undersides of the leaves. Just spray it ON the leaves and it kills eggs and mites right through the leaves. Because it works systemically, it can only be used in vegetative phase. It keeps killing for about 40 days. That's almost 7 weeks. It's great stuff.
I had a two year long infection. Tried everything under the sun, they always came back. Sprayed once with forbid during vegetative and no more mites. I did spray the floor and sides of the buckets a few weeks later to get rid of any hiders. I also sprayed my house plants.
I have not seen a mite since. I used it once during vegetative stage on each crop for the next six months. I also sprayed them when they were rooted cuttings. NOW I just spray the rooted cuttings before they go into the system for prevention.
Forbid is super expensive. Like $400 a pint and 1 ml makes 1-2 gallons. It is super potent stuff. You can buy small amounts online for $15 - $25. I bought 4 ml on ebay in a little vial with a 1 ml measuring pipette for $15. I am still on the first gallon, a year later. I have used 1 ml and that's all. I still have enough left to make 3 -6 gallons. Best $15 I have ever spent.
You can NOT use it during flowering, but it keeps killing for so long that it isn't necessary. It wipes them out with one application.
http://www.ebay.com/itm/Forbid-4F-spidermite-formula-1oz-Free-Lightning-fast-shipping-with-tracking-/251180415792?pt=LH_DefaultDomain_0&hash=item3a7b84fb30