“What is the best antifouling for fresh and saltwater?” is a question whose answer seems simple but still depends on the user. Does the buyer want the cheapest antifouling paint? Does a boat sail a lot or a little? Should antifouling last at least 8 years? Does the environment play a role in the choice? Various factors play a role in discovering the best antifouling.
It is just like with wine. What is the best wine? That question always leads to an interesting discussion because of so many people and so many tastes. A simple Côte de Provence from 2024 can make someone just as happy as a sommelier who uncorks a Petrus from 2005. The developed taste buds, the sense of smell, the dishes, the budget and with who the wine is drunk are decisive external factors that also determine the choice. Once you have made a choice, there is a good chance you will choose that wine again next time.
What is the best antifouling for fresh and saltwater?
It is the same with antifouling; if you like it, you choose the same brand every year. Until the government bans its sale. Then you are forced to look for a new product, something that suits your situation.
Anyone who does not care about the proven fact that traditional antifouling leaves toxic skid marks in the sea can go for the poisonous version without any scruples. Until the shipyard decides to no longer work with environmentally harmful antifouling paint. Those who are not afraid to experiment with new technology can fortunately choose from a wide range of alternatives, from ultrasonic to copper plates. We list the options for you, including the advantages and disadvantages.
All types of antifouling
Antifouling is the process of preventing marine organisms such as algae, barnacles, and molluscs from attaching to underwater surfaces, such as a ship’s hull. Effective antifouling helps prevent drag and fuel consumption from increasing and speed and overall performance from decreasing.
-
Biocidal antifouling paints
These coatings contain biocides (chemical compounds such as copper, zinc, or organic compounds) that prevent marine organisms from adhering to the surface. They come in hard and self-polishing varieties. With hard paints, only the biocides dissolve. Self-polishing paints also enter the water as microplastics.
Advantages:
– Effective in preventing fouling.
– Easy to apply.
– A wide range of formulations are available for different water conditions.
Disadvantages:
– Biocides are toxic to marine life and cause environmental pollution.
– The paint dissolves as microplastics.
– Many countries and regions ban certain biocides.
– Short lifespan, often only one sailing season.
– Requires periodic reapplication, which involves labour and expense.
EMSA on toxic biocidal antifouling paint
-
Biocide-free coatings
There are also coatings on the market that do not contain biocides but that dissolve slowly.
Advantage:
– They do not contain biocides.
Disadvantage:
The paint does dissolve as microplastic. It also often contains zinc, which is not always considered a biocide but is a heavy metal that should not end up in the water.
National Library of Medicine on biocide-free antifouling coating
-
Non-stick or foul-release coatings
These coatings create a smooth surface, making it difficult for organisms to adhere. They often use silicone or synthetic fluoropolymer bases. Sometimes, these coatings are combined with hydrogel technology.
Advantages:
– More environmentally friendly because they release fewer to no toxic substances.
– Can be easier to clean compared to biocide-containing paints.
– Good for reducing resistance and improving fuel efficiency.
Disadvantages:
– Less effective in areas with much fouling and requiring frequent cleaning.
– Application requires specialised professionals.
– Old antifouling must be removed, sometimes resulting in higher initial costs than traditional paints.
– There are indications that toxic substances are still released into the water that have been banned since 2008
– Coating discolours faster, making it less aesthetic.
– Recycling is impossible.
– All of these coatings contain PFAS.
Marine Pollution Bulletin on Silicon Foul Release Coatings
-
Electrolytic systems
These systems use an electrical current to create an environment that discourages marine life growth, often by releasing small amounts of copper or other ions.
Advantages:
– Can be effective over a long period with proper maintenance.
– Suitable for areas with minimal to moderate fouling.
Disadvantages:
– Still toxic.
– High initial installation costs.
– Requires continuous power and maintenance of electrical components.
– Effectiveness may decrease in very polluted water.
American Meteorological Society on Electrolytic Antifouling
-
Ultrasonic Antifouling Systems
These systems use high-frequency sound waves to disrupt marine organisms’ ability to adhere and prevent them from settling on the hull.
Advantages:
– Non-toxic and more environmentally friendly.
– Minimal maintenance after installation.
– Effective on a variety of boat sizes.
Disadvantages:
– Harmful to whales and other animals in the area (see Scripps link)
– Effectiveness can vary, especially in areas with heavy fouling.
– High initial cost and energy requirements.
– May not work well on all types of fouling, especially heavy barnacles.
Scripps Institution of Oceanography on Ultrasonic Antifouling
-
Regular Cleaning
This involves manually removing fouling regularly using brushes, scrapers, or high-pressure cleaners. Some vessels use divers for this purpose. Various robots are now available for yachts. Another method of regular cleaning is the use of brush lanes. These work just like a car wash: you sail your boat through them and come out clean.
Advantages:
– No chemicals, so safe for the environment.
– Flexible schedule, can be done as needed.
– Cheap compared to high-tech options.
Disadvantages:
– Labor-intensive and time-consuming.
– Limited effectiveness because it requires regular attention.
– Not realistic for larger vessels.
Healthline on strengthening muscle mass
-
Natural antifouling coatings
This antifouling coating uses natural extracts (such as capsaicin from chilli peppers or other plant substances) to prevent fouling. Milk fat is also used as a protective layer.
Advantages:
– Environmentally friendly with minimal impact on the environment.
– No risk of chemical build-up in water.
– Growing interest in natural solutions supports continued innovation.
Disadvantages:
– Limited effectiveness compared to synthetic biocides.
– Still in development, with few options commercially available.
– It may require more frequent recoating than other methods.
MDPI on Water-Based Antifouling Coating with Capsaicin
-
Finsulate Antifouling Film
Finsulate is a new type of antifouling rapidly taking the world by storm. Finsulate is a non-toxic, physically acting film applied to the hull as a self-adhesive layer. Finsulate not only looks good, the film’s structure is highly effective against the growth of organisms such as barnacles and algae.
Advantages:
– Environmentally friendly and non-toxic, as it does not release chemicals into the water.
– Long-term protection with an eight-year warranty.
– Aesthetically beautiful due to deep black material.
– Low maintenance and easy cleaning because the fouling does not stick.
– Can be applied to various types of vessels, from recreational boats to large commercial ships.
Disadvantages:
– The old antifouling must be removed, sometimes making the initial costs higher than traditional paints.
– Requires professional installation to ensure good adhesion and effectiveness.
Finsulate distinguishes itself through its sustainable approach to antifouling, combining long-term effectiveness with minimal environmental impact. It was developed as a greener alternative to conventional antifouling paints, but it is also widely purchased because it provides the buyer with long-term peace of mind.
Searching for the best eco-friendly antifouling for fresh and saltwater
Once you have opted for an environmentally friendly antifouling, you are on the right track as far as we are concerned. We are satisfied as long as no poison is used and no microplastics from the paint end up in the water. But if you want an antifouling that will last at least 8 years, has won many Innovation awards and is proven effective, then we naturally hope you will end up at Finsulate.
We take care of the professional application to guarantee that you can enjoy Finsulate for at least 8 years. This way, we know for sure that everything goes well. We increasingly have shipyards do this because they can more easily plan it into the rest of your yacht’s maintenance.
A long road to the best antifouling
The materials scientist Dr Rik Breur has always been very interested in biology and has gained much knowledge of marine biology. Inspired by the prickly sea urchins, Rik developed a special self-adhesive foil; Finsulate was born. In 2019, based on his worldwide patents, he won the prestigious European Inventor Award.
Since 2014, more and more boats have slowly been equipped with Finsulate. The more boats were covered and the longer the boat owners enjoyed Finsulate, the clearer it became that Finsulate was an unprecedented revolution in antifouling. The product and production method were further optimized over time also to cover large work vessels and offshore installations.
There are now four versions of Finsulate on the market: fresh water, salt water, high speeds, and passive installations (offshore). The production capacity is scalable, so Finsulate is now the best choice in environmentally friendly antifouling worldwide. In 2024, Finsulate was listed in the Twenty Most Innovative Companies to Watch.
