A portable battery-powered ozone generator, or ozonator, contained in a waterproof housing with an air intake and an ozone discharge conduit diffuses ozone directly into a body of water in a pool, pond or tank. The ozone generator and housing can be part of (1) a buoyant floating platform that is also equipped with solar power collector panels to provide a recharging current for the battery; (2) a robotic, self-propelled pool cleaner; or (3) a skimmer filter assembly that can include a solar panel under a solar transmissive cover that is flush mounted in the walk area alongside the pool.