I've posted this before I think, but everyone who uses this system loves it.
Bring about 10 pieces of burlap and replace when they are jammed up with crud (you can scrape off some non obnoxious stuff like coffee)
Put a capfull of bleach in the filtered water and just take it home with you. Putting it in a standard evap pond could make a stink.
Link below has more info:http://goo.gl/QU3VI
Here are some pics from the link: