The conclusion of the experiment conducted on sea anemones and corals is that they have a symbiotic relationship with zooxanthellae, a type of algae. The zooxanthellae provide the anemones and corals with nutrients through photosynthesis, while the anemones and corals provide a protected environment and access to sunlight for the algae. This symbiotic relationship is crucial for the survival and growth of both the anemones/corals and the zooxanthellae.