If you don’t know what bottom paint is, you are not alone. A boater that keeps his/her boat in the water for an extended period of time, must have bottom paint on the bottom of the hull to prevent growth (fouling) from occurring.
Bottom Paint, also called antifouling paint, boat bottom paint, and anti-foul paint, is a special marine paint that is formulated with pesticides to keep those marine critters from growing on the bottom of the hull. Copper is most common pesticide used in bottom paints, and will prevent hard growth. Hard growth is considered mussels, barnacles, or any other crustacean that can attach to the bottom of the boat. Hard growth mostly occurs in warmer water and salt water. However, depending on your geographical location, hard growth will occur in fresh water and nutrient rich cool waters as well.
Some boat bottom paint is also combine other pesticides (biocides) with copper to prevent soft growth. Soft growth refers to algae and grass.
Why do you need bottom paint? If you are going to keep your boat in the water for more than a couple of days, you will need some bottom paint!