"The carbon in these things is a miracle; I can't smell anything from my fish tank anymore. They also don't allow any debri bypass because of how thick the floss is and do a great job of keeping the water crystal clear. And, you can simply hose 'em off with a power hose or slosh 'em around in used tank water and they're good as new.
Below is a vid to show how clear my 20 gal. tank is because of these (the sound is from an AquaClear)."