When choosing an antifouling bottom paint, does it matter how often I use my boat?

Antifouling bottom paints prevent marine fouling organisms from clinging to the bottom of your hull. If you use your boat often, but store it out of the water between uses, there's really no need to apply antifouling paint because barnacles and weeds won't have time to take hold.

How often you use your boat is just one of the many factors to consider when choosing an antifouling paint. If your boat stays in the water during most of the boating season, or all year long, application of bottom paint is pretty much a given. So, how often do you use your boat?

I use my boat often: An ablative antifouling paint is a good choice for boats that see frequent use because ablative bottom paints slough off gradually as water moves under the boat (either at the dock or underway), continuously releasing a fresh layer of biocide. An added benefit of ablative paints is that there's no paint buildup, so there's less work to remove old layers of paint before applying bottom paint the following season. Examples of ablative antifouling paints are TotalBoat JD Select and Sea Hawk Monterey.

I keep my boat in the water year-round: For a boat in the water year-round, you need long-lasting protection in potentially high fouling conditions. Your best bet is a hard bottom paint, which forms a tough coating that holds up well, doesn't wear away, and leaches biocide on contact with water. It's the copper biocide that wears away gradually, instead of the paint, until all the biocide is depleted. Examples of hard bottom paints are Pettit Trinidad HD, Pettit Trinidad Pro, Interlux Ultra, and Sea Hawk Tropikote. The downside is that you still have the original thickness at the end of the season, and eventually you will have to strip it before the next bottom paint application.

I use my boat infrequently: In this case, you want an antifouling paint that will maintain its barnacle-battling properties even when the boat is inactive, such as a copolymer ablative paint. After applying, you can haul and relaunch your boat without losing the effectiveness of the biocide, and without having to repaint. These paints have no maximum dry time to launch after application. Examples include Pettit Hydrocoat, Interlux Micron Extra, and TotalBoat Krypton.