3 ms·Nothing lasts in sea water. Least of all sponges. I doubt that's a practical application.by waps 12y agoNothing lasts in sea water. Least of all sponges. I doubt that's a practical application.kordless 12y agoJust wash it off.waps 12y agoIncidently, detergent is one of those things that won't work well in seawater. Plus seawater is corrosive. So even if you do manage to clean things, they're not as reusable as they otherwise would be.