Good Stunt. Bottom paint protects your hull from growth, but what about the other parts of your boat that retain water? How do you keep them free of growth? Most boaters wait until midseason before scraping away any barnacles and algae, but a little extra work now can thwart the intruders. For example, you can't put bottom paint on depthsounder transducers, but they need special protection, so apply a coat of Pettit transducer paint ($25; www.pettitpaint.com). Other items below the waterline that can be fouled-the insides of seacocks, raw-water intake grates, and so forth-should get a smear of Boat Armor Easy On Bottom Coating ($47; www.westmarine.com). It lasts only a few weeks, but this wax-like coating can be applied underwater, so you can reapply it throughout the season.