Corrosion is the main reason every vessel needs cathodic protection, whether it cruises in sea, brackish or fresh waters. Sacrificial anodes are the best solution against corrosion. But, certain attention needs to be paid regarding which alloys are being used and how to choose your sacrificial anode manufacturer wisely.

Hopefully this article answers the question. Let’s dive deeper into what it means to choose the right anode type for your ship, and how to find a manufacturer that cares to provide anodes made from the purest materials.

Choosing the right anode type

Choosing the right type of anode to install on your vessel depends on five main factors:

  1. the type of application
  2. the environment
  3. the material of the structure being protected
  4. the standards that should be followed
  5. the anodes’ size and shape

Different types of anodes are suited to different types of applications. For example, aluminum anodes work better in freshwater environments. On the other hand zinc anodes are preferred for saltwater environments.

Other environmental conditions like water temperature and pH, also play a role in selecting the right anode.

Moreover, it’s important to consider the compatibility of anodes with the metal of the hull, ensuring that the anode installation will not cause any damage to the parent metal. After all, attaching anodes to the hull takes place to protect it, not damage it further.

Last but not least, anode size and shape should match the surface area and shape of the protected structure for optimum results.

Aluminum or zinc anodes and why

NIKA anodes by Katradis S.A.
NIKA anode by Katradis S.A.

Aluminum and zinc are both commonly used as anode materials for vessels. Both materials are effective at protecting the vessel’s hull and underwater equipment from corrosion. But there are some differences to consider when choosing between them.

Aluminum anodes are generally less expensive than zinc anodes and have a higher driving voltage. This means they are more effective at protecting the vessel in highly corrosive environments. They also have a longer lifespan than zinc anodes and tend to be less affected by changes in temperature and pH.

Zinc anodes are more expensive than aluminum anodes, but have a lower driving voltage. This makes them less effective in severely corrosive environments. They also have a shorter lifespan than aluminum anodes and are more sensitive to temperature and pH changes. On the other hand, zinc anodes do not produce hydrogen gas while corroding. This feature could be a reason to decide upon zinc for safety reasons in certain situations.

Ultimately, the choice between aluminum and zinc anodes depends on specific needs and requirements related to the vessel and the environment in which it operates. Apart from the five main factors discussed earlier in this article, the cost and anode availability are also things to consider before reaching a decision on replacing your anodes.

How to choose the right sacrificial anode manufacturer

When choosing a sacrificial anode manufacturer, it is important to consider the following factors:

  1. Quality of the anodes: Look for manufacturers that use high-quality and high purity raw materials, and manufacture anodes under processes with strict quality control protocols.
  2. Experience and expertise: Choose a manufacturer with a proven track record of producing high-quality anodes and has experience in the specific application you are going to use them for.
  3. Customer service: Look for manufacturers that provide excellent customer service, including technical support and fast response times.
  4. Pricing: Compare prices from multiple manufacturers to ensure you are getting the best deal. Lower prices don’t always mean you are getting the best deal though. Try to find “value for money” options.
  5. Certification & warranties: Look for manufacturers that have certifications from relevant organizations like American Bureau of Shipping (ABS), Lloyds Register (LR), DNV GL, etc.
  6. Carefully selected suppliers: Some manufacturers may have their own mines or they may hold long-term agreements with mines to secure lasting supply of good quality raw materials (very important for supply continuity).
Casting anodes with pure materials at Katradis factory
Casting anodes with pure materials

Sacrificial anode manufacturer vs third party supplier – Where to buy from?

Is there actually a difference between buying from a supplier versus buying from a manufacturer?

Actually there is! Always prefer the sacrificial anode manufacturer because they have the most accurate and up-to-date information on their products. They are able to provide detailed information on the quality, composition, and performance of their anodes, as well as any certifications or standards these products meet.

Additionally, by contacting the manufacturer directly, you can be confident you are getting the original product – not some counterfeit or inferior product that may not perform as well.

More than that, sacrificial anode manufacturers collaborate with tech experts and researchers who can guide you in choosing the right anode for your specific application. These experts will also advise you on how to properly install, maintain and replace the anodes.

Vasilis Petrakis, metallic materials experts

Finally, by buying directly from the manufacturer, you may be able to negotiate a better price and have access to a bigger stock. This means you won’t need to sacrifice quality over quantity!

In any case, it’s worth mentioning that when you purchase anodes from a distributor or third-party supplier, you may not have access to the same level of technical support and may not be able to verify the authenticity of the product. This can lead to potential safety risks or
damage to your equipment.

Katradis S.A. – Quality products for maritime globally

Katradis S.A. establishments

Maintaining and enhancing our credibility globally, we have for a long time now committed to provide only high quality products in accordance to the requirements of our customers and international specifications.

Our anodes are casted carefully within our establishments and the whole process is being monitored by our experts. This way we are certain that our anodes meet quality standards and are appropriate for marine use.


Katradis S.A. offers products and solutions for marine operations. Apart from top quality anodes you may find wire ropes, mooring ropes, lashing equipment and port infrastructure. Follow us on Facebook, Instagram and LinkedIn and keep in touch with us to learn more about our methods in control testing, optimum product applications and marine related advice.