Don't these things need to be washed after a while? Don't have one but am now thinking of getting one...but lookind at how much fouling is comes out on patches those things must be solid black after 2 or 3 cleanings. How do you go about washing them if they have the oily solvents in them. Will detergents left on the snake harm the metal (doubt it, but should check while I'm at it, right?)