The manual has pretty good directions for that too.
That's how I found them. I was wheeling in some smelly swamps and for the next 2 weeks my X smelled like sh*t. I looked it up in the manual, took them out, cleaned them with fresh water, let them dry and put them back in. The water had gotten to them. It was pretty deep and I was wheeling with the AC on. I guess it sucked it up.
Maybe just above the tires but I was hitting it with alot of speed. When I get nervous and think I may get stuck I tend to hit the gas. I'm trying not to do that anymore.
As far as the wash and reuse, That was before I found this site and I went to Pepboys but they didn't have it. I didn't know where else to buy it and I was afraid the dealer would want to know how I got it so dirty in 2 months, plus charge me some crazy amount for it. So that's why I did the wash and reuse.