What is galvanic corrosion, and how do you prevent it?

It sounds technical, but the idea is simple and the defense is straightforward. A little understanding here protects some of the most expensive metal on your boat.

What’s actually happening

Seawater conducts electricity. When two different metals — say a bronze prop and a stainless shaft — sit in it, they form a weak battery, and current flows from one to the other. That current carries tiny bits of metal away from the more vulnerable part. Over time, unprotected running gear pits, weakens, and fails. It’s slow, quiet, and entirely preventable.

Your defenses

• Sacrificial anodes, which corrode in place of your prop and shaft — the first line.
• A sound bonding system, tying underwater metals together so anodes can protect them all.
• Clean, dry wiring, since stray current from electrical faults accelerates the damage.

Why some marinas are worse

In a crowded marina, current can leak from nearby boats and shore power into the water — called stray-current corrosion — and attack your gear faster than galvanic action alone. The practical defense is the same: keep your anodes healthy and have them checked regularly. A diver who inspects your anodes on every visit catches accelerated wear before it reaches the parts that matter.

Want a number for your boat? See an instant estimate at mistingmonsoon.com/calculator, or call 727-344-9848 and we’ll set your first dive.