For a more long term solution you can use Nix lice bedding spray from HEB, just take everything out of the cage, spray it evenly then let it dry for 30 minutes before replacing the substrate, water bowl, and snake. It kills all stages of snake mites and last for awhile. I started using it and havent seen a mite in 2 months and I had a couple of snakes with a severe infestation that I picked up at a local pet store. Hope this helps.
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Dustin Smith