[Gerry Zagorski]

Bill - I usually hit mine with a scotch pad you can pick up in any paint, boat or hardware store. They are made of the same scrathy material as the back and rougher side of kitchen sponges.

Once you get all the crud off, make sure you get all the dust off and coat with transducer paint. It's OK to use bottom paint on the sides of the ducer but you want to use ducer paint for the running surface. Most boat stores carry it in their paint section and sell it in small white bottles.

Hope that helps.