Hypoaspis (fungus gnat control)
"Hypoaspis is a predatory mite that lives near the soil surface and feeds on fungus gnat larvae and thrips pupae.
Hypoaspis are dispatched in an organic mixture that should be evenly scattered over the treatment area or spooned into the base of pots. The mites then migrate into the potting media and feed on soft bodied pests in the root zone." - from the site .
It says they feed on fungus gnat larvae and thrips pupae- nothing about other mites. It also says the mites migrate into the potting media (soil). I dont see how from this description that they would eradicate snake mite.