Why Change from Zinc to Navalloy® Anodes?
Many professionals in the marine industry stick with zinc anodes because that’s what they have always done. Zinc in its natural state works quite well as a sacrificial anode so that’s what has been used for centuries. That’s why we call them zincs. But there is a better solution now –Navalloy® anodes.
We often hear the question “Will they work in salt water” and the answer is “Yes! Absolutely!” Most outboard manufacturers have switched to aluminum. The Navy is switching and pipelines and oil rigs universally use aluminum alloy anodes in the ocean.
Zinc is OK in salt water, but in fresh or even brackish water it stops working. It coats over and insulates itself. It is also a toxic metal and has been identified by the EPA as a source of contamination in and around marinas. As a result, Maryland has proposed banning zinc anodes and the EPA changed its vessel general permit requirements for larger vessels to “select ... metals that are less toxic to the extent technologically feasible and economically practicable and achievable’ and recommend switching to aluminum alloy anodes.
As far as doing the job of protecting from corrosion, aluminum alloy anodes are hands down better than zinc ones in all applications. They work at a slightly lower voltage (giving better protection), last longer, and work in any type of water (tested by ABYC), in addition to being 20 times less toxic than zinc anodes. They are usually less expensive as well!
Use in any water:
Performance Metals is the leading US manufacturer of aluminum anodes made to the military specification MIL-DTL-24779.