Then San Diego diver Van Johnson showed me a trick. Before attaching a shaft or prop zinc, paint a 1-centimeter stripe of nail polish on the zinc adjacent to the screw socket. The paint prevents just that surface area of the anode from dissolving, extending the effective lifespan of the zinc, thereby preventing waste and saving money. And remember, don’t sink or dump used zincs; recycle them. Many marinas have collection sites for used anodes.