If you use your boat in saltwater conditions, you want an antifouling bottom paint that will be effective against all the barnacles, zebra mussels, algae, slime, and plant-based hitchhikers that will attach themselves to the bottom of your boat. Good choices for saltwater antifouling conditions are Interlux Micron 66, Interlux Micron CF, Pettit Trinidad HD, Pettit Premium HRT, Sea Hawk Smart Solution AF, Blue Water Marine Copper Pro SPC, and TotalBoat Spartan.