Snake Mites

Question
Hello,
I was wondering about you opinion about what to use on snake mites I have been fighting with these mites for the past month and a half and they seemed to be coming back each time.  I have eight snakes all have their own tanks, I only see them on five of the eight snakes but I treat them all.  I have already used Mite-off from a zoomed product, The Nix head lice solution, and ivermectin solution I got the ivermectin from the vet it kills the mites because I can see them on the paper towels but this doesnt seem to do anything in the long run, the five snakes are younger ones under a year old these are the ones that get it the worse as the bigger snakes don't seem to have it but I treat them still, the vet didn't want to inject them with the ivermectin because he said if they are allegic to it there's nothing you can do once you do the injection it's not like you can take it away, so he gave me the liquid medication to dilute in water because he said if any signs of reaction you can stop using it and wash it off and since they are younger snakes the vet didn't feel confident to inject them.  I was wondering if you ever had been in this situation before and if you have what methods do you use and what medication have you used?  Every TUESDAY I give them a nix bath and spray I was following this guys video http://www.youtube.com/watch?v=oqziwNaosQM  and the second video  http://www.youtube.com/watch?v=GyMzc0Wljsw   and third video http://www.youtube.com/watch?v=M0ScAjJg4D4  its a three part video sorry if I'm taking up so much of your time, Then on Every FRIDAY I use Mite-Off, been doing this for the past month and a half.  I clean out the paper towels once a week and I take the tanks out side once a week for a complete hose down and spraying with nix, it's been a pain because the tanks range from 40 gallons to 125 gallons.  What do you think I should change my routine because I know I'm doing something wrong it's not working.  Thanks

Answer
Thomas,
  Here is what I would do. Remove all 8 of your snakes and slather them daily with the generic form of nix, leave for 5 min, then wash it off. It is cheaper than the brand name. House them in Rubbermaid tubs during this process. Stay with this until you see no mites, then wait another week to make sure that eggs on the snake have not hatched. Meanwhile, use a mixture of Invermec (you can buy it online) and good old fashioned sevin liquid from walmart. Mix them in a sprayer diluted with water and hose down your cages. Leave them for the entire time, in fact, it would be a good idea to put them outside. Once this is done, all the snake are clear of mites for 8 days, introduce 1 snake at a time to his enclosure (after you have washed off the sevin / invermec with a bleach and water solution, then rinse with pure water. Wait 3 days and make sure you have no more mites with that 1 snake in that 1 enclosure. If it is all good, repeat the process with another snake until you are all clean. It takes forever and mites are the devil to get rid of, but this method has worked for me.