Our recommendations can be found on the blog post What is the Best Masonry Paint?

"Keim Royalan, applies on all mineral substrates and is formulated for use in extreme conditions. It is more resistant to fungal and algae growth that are more prevalent in humid and coastal environments, with all of the properties and benefits of mineral paint. Because of how harsh coastal conditions can be, Keim Royalan requires specification before purchase and is therefore only available as “price on application” – visit the product page to see more details, find data sheets, and to contact our technical team to discuss your requirements."