Anode

An anode on a boat is a deliberately sacrificial metal fitting used to protect underwater metals from galvanic corrosion. Usually made from zinc, aluminium, or magnesium, it is electrically connected to components such as a propeller shaft, saildrive, rudder stock, through-hull, or engine cooling circuit so the anode corrodes first.

Anodes matter because salt water, stray current, and dissimilar metals can quickly damage expensive hardware. A wasted anode can leave the Hull, Rudder, or propulsion gear exposed, affecting safety, reliability, and fuel efficiency. Boats connected to Shore Power need particular attention, as marina electrical faults can accelerate corrosion.

Check anodes during haul-outs, before long passages, and after time in unfamiliar marinas or warm, highly saline water. Replace them when around half consumed, and use the correct material for salt, brackish, or fresh water. PredictWind forecasts can help choose a calm weather window for inspection, diving, or a lift-out.