Currently boats are pulled up out of the water, scraped clean and painted with new anti-foul. My idea is to create a pool full of algae & weed eating life, the boat drives in, stays there for a day, and drives out the other side. The fish stay in because they get a constant supply of food, the boats don’t need the expensive boat ramp to pull it out of the water to work on it, lower the cost because there isn’t the anti-foul and labour, and we increase our biodiversity and life density.
Perhaps I would teach seals (maybe otters?) to wield scrapers to knock barnacles off and eat them up. Either that or drones.