Np, and and that's usually the first thought when we find something in the ocean, but sadly bringing a seashell or rock from the ocean can carry bacteria and/or other bad hitchikers with it that can wreck a home sw aquarium, just soak it by itself and make sure there's nothing coming in with it
If its a seashell, I'd do freshwater, as that should kill any bacteria or anything, try running hot water for a few minutes