Hm.. the mties that I have seen, were small black things. I don't know what yours are, since you said a) they are clear, and b) they're not on the snake.. by the time it was so bad that I saw them in our water dishes, you could plainly see one or two on the snakes themselves.
PAM works wonders. I wou'd treat with it as a general precaution when getting any new snakes; just simply follow the directions on the can, and life is good.