You understand the importance of an ACTIVE anode (if not, go back to week #7). Here are some common installment errors and some specific “change of environment” circumstances that can cause an anode to become inactive or less effective.


Layer of paint – This is a big one! Especially when you haul your boat out for new bottom paint. If there is a layer of paint on the metals you are trying to protect (your trim tabs, the strut or the bolts that attach a hull plate to the hull) that will impede the flow of ions between your anode and those metal boat parts. The paint may appear to protect those parts at first, but the metal can still corrode under the layer of paint. Over time you will see the paint start to blister, but know this, once you see it, the damage will already be done. Similarly, if there is paint on the actual anode, that barrier will impede the flow of ions rendering the anode useless.

Layer of growth – If there is any marine growth, even something you can’t see, it will cause a barrier between the two metals and the circuit will be less effective since you lose the metal to metal contact. Any piece of metal on your boat should be cleaned and sanded at the anode attachment point to make sure there is direct metal to metal contact.

Layer of oxidation/corrosion – Just like marine growth, a small layer of oxidation, rust or corrosion on the anode attachment site of the metal you are protecting (trim tab, shaft, propeller) will cause a barrier that will not allow the flow of ions between the anode and the cathode to be as efficient. The anode may still work, but will be less effective and that means you’re not getting your money’s worth.

Make sure before you splash your boat after a haul out or at the start of a new boating season that the metals on your boat are sanded down at the anode attachment site so they can work effectively to protect your boat while you’re enjoying it!


Dingy or motor storage – If you have anodes on your dingy or on an outboard motor that you take in an out of the water, you can expect those anodes to lose effectiveness or stop working all together over time. Be sure you’re keeping a close eye on the metals that go in and out of the water. If you see signs of corrosion, you know it’s time for new anodes.

Dry docking – If you haul out or store your boat in the off season, your anodes from last year will form a crust or barrier, even if you can’t see it, not allowing them to do their job when you put your boat back in the water.

Haul outs – Any time you have work done on your boat that takes it out of the water, you should plan to put all new anodes on your boat before it goes back in the water. Remember, if you have your hull painted, be sure the yard sands the paint from the anode attachment site before installing new anodes.

These tips will help to be sure your anodes are active and working to protect your boat. 

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