I've also heard that using crisco can be harmful or damaging to a snake. I had one case of mites recently that I had to deal with for the first time in 10 years of keeping herps. I followed the directions of some friends and it worked out great.
I soaked the new quarantined snake (which was a argentine boa) in a mild soapy water solution for about 1-2 hours in a 5gal bucket. The soapy water will help to break down the mites exoskeleton. Meanwhile, I sprayed her entire enclosure (and I mean everything) with Provent-a-Mite. This stuff is harmful to snakes in its gasous or liquid form, but okay if you allow it to dry, which happens while the snake is taking a bath.
I even found mites under the inside lip of the water bowl so I even sprayed under there. The only place I did not spray, was in the water bowl itself for obvious reasons.
After the Provent-a-Mite dried and the snake has soaked, I removed the snake from the 5gallon bucket and sprayed a papertowel with stuff called Reptile Relief which I then rubbed onto the snake. I bought the provent-a-mite & repti-relief from Big Apple herp and it arrived fast. It was well worth the cost since I have not seen a single mite in 4 weeks since after this method of treatment.
Using oil can be harmful and cause actual scales to slough or fall off, which looks gross from pics I've seen.
BLACK KNIGHT...I have been told works well BUT is NOT AVAILABLE due to a law suit possibly involving the toxic effect of one of its ingredients (but I'm not totally positive). Someone told me that the company has a whole warehouse full of the stuff since the company did not stop production right away when their legal troubles hit.
Tell your friend good luck!
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