How Often Should a Yacht Be Serviced Underwater?

Monthly. For yachts kept in warm saltwater, a diver in the water every three to four weeks is the standard. That keeps marine growth soft enough to remove with gentle tools and ensures zincs, through-hulls, and running gear get checked before problems develop.

Barnacle Busters puts the majority of its yacht clients on monthly programs for this reason.

Why Monthly Works

Water temperature drives biofouling speed. In cooler climates, boats can go six to twelve weeks between cleanings during winter. In warm saltwater above 20°C year-round, there's no slowdown. A yacht left for six weeks will have significantly more fouling than one serviced every four. Monthly visits keep growth in the soft stage, where it comes off without damaging the antifouling coating.

When You Might Need It More Often

Yachts in areas with poor water circulation, like enclosed canals or the far end of a marina basin, tend to foul faster. Vessels that sit idle for weeks between uses also accumulate growth more quickly. Shore power connections add another variable: stray current from shared dock grounding can accelerate zinc depletion beyond normal rates.

If your diver is consistently finding heavy growth or depleted zincs at monthly visits, a three-week cycle is worth considering.

When You Might Stretch It

Yachts in cooler or brackish water may go five or six weeks during colder months. Vessels that run frequently at speed benefit from some natural cleaning effect. But the running gear and through-hulls still need attention on a tighter schedule than the hull itself.

The Alaska Sea Grant Marine Advisory Program lists keeping the bottom free of marine growth as one of the most effective ways to reduce fuel waste. That advice holds everywhere, but the required frequency increases with water temperature.

Contact Barnacle Busters to discuss the right schedule for your yacht.