As a boat owner, getting dragged to the depths of the ocean by a giant sea monster is probably not high on your list of concerns. But make no mistake, there are some very foul creatures lurking beneath the waves.

We’re talking microscopic sea monsters: acorn barnacles, zebra mussels and slime-causing bacteria that cause serious hull drag, and wallet drain from higher fuel costs and repair bills.

You may not even know they’re there until it’s too late because they don’t come at you flailing ferocious tentacles, at least not ones you can see. What you will see—and want to prevent—is the ugly, dirty, slimy mess they make on the bottom of your hull that decreases your speed and increases your fuel bill because your engine has to work harder. A fouled hull bottom is also a safety risk because it can decrease your ability to maneuver.

Battle the barnacles and other biofouling bottom huggers with the right bottom paint for smoother sailing.