Zinc or Aluminum?
Fewer items on a boat can outweigh the importance of a properly working set of anodes. Anodes have been a hotly debated topic for several years now. Last season, Herrington Harbour began promoting aluminum anodes over the traditional zinc anodes. Several factors went into making this decision. The two biggest reasons were performance and cost.
Aluminum outperforms zinc anodes by a staggering 3 to 1 ratio! On average, an aluminum anode will protect against 3x the stray current damage that a zinc anode can withstand. This increase in performance is achieved without the use of the carcinogen, cadmium. Cadmium is a seagrass growth inhibitor and is recognized by the National Cancer Institute as a harmful element associated with lung cancer. On the other hand, aluminum is the most abundant mineral on earth and considered to be safe for all levels of exposure.
In the past, the cost of aluminum anodes far exceeded that of zinc anodes. With more demand for the products and the increase in production, the price has come down significantly. In many cases, the aluminum will be the same price or less than zinc anodes.
This year, when you are choosing your anodes, don’t just take our advice, look into them on your own and make a decision that works best for you. If you spend the majority of your time cruising the Chesapeake Bay, aluminum anodes are the way to go. For areas with higher concentrations of freshwater, magnesium anodes are superior. For blue water cruising and higher salt concentrations, zinc anodes are better.