When it comes to mites you have so many things to choose from to kill them I know ppl say lady bugs eat spider mites but they dont thats from personal exp.
You can go out and buy some Neem oil, or Dawn Dish soap original use a cap full per spray bottle the 56oz ones, You can also Buy this spray call Lady Bug Works pretty good, You can also buy Something with pyrethrin in it that works...
There is a endless list of things you can do, A simple Spider Mite Control search in google will tell you everything you need to know.
Best of luck hope you get them out before to long.